WO2011152466A1

WO2011152466A1 - Carbazole compound having substituent group including electron-accepting nitrogen-containing heteroaryl, and organic electroluminescent element

Info

Publication number: WO2011152466A1
Application number: PCT/JP2011/062620
Authority: WO
Inventors: 洋平小野; 国防王
Original assignee: Jnc株式会社
Priority date: 2010-06-02
Filing date: 2011-06-01
Publication date: 2011-12-08
Also published as: KR101864902B1; KR20130112690A; JP5783173B2; JPWO2011152466A1; CN102918037A; TWI538910B; TW201202216A; CN102918037B

Abstract

The purpose of the present invention is to provide an organic electroluminescent element in which the drive voltage and the longevity of the electroluminescent element are excellent. A carbazole compound represented by formula (1-1) is used as an electron transport material to manufacture an organic electroluminescent element. (In formula (1-1), R is an aryl or a heteroaryl, Hy₁ and Hy₂ are each C2-24 electron-accepting nitrogen-containing heteroaryls, and Ar₁ and Ar₂ are each C6-24 arylenes.)

Description

Carbazole compounds having substituents containing electron-accepting nitrogen-containing heteroaryl and organic electroluminescent devices

The present invention relates to a carbazole compound having a substituent containing an electron-accepting nitrogen-containing heteroaryl, an electron transport material, an organic electroluminescent element, a display device, and a lighting device using the same.

2. Description of the Related Art Conventionally, display devices using light emitting elements that emit electroluminescence have been studied variously because they can save power and can be thinned. Further, organic electroluminescent elements made of organic materials can be easily reduced in weight and size. Therefore, it has been actively studied. In particular, the development of organic materials with light emission characteristics such as blue, which is one of the three primary colors of light, and organic materials that have charge transporting ability (such as semiconductors and superconductors) such as holes and electrons The development of materials has been actively studied so far, regardless of whether it is a high molecular compound or a low molecular compound.

For example, an organic electroluminescent device using a compound in which an aryl-heteroaryl such as a pyridyl group is substituted on the central skeleton of anthracene has been reported (Japanese Patent Laid-Open No. 2003-146951; Japanese Patent Laid-Open No. 2005-170911). Gazette; Patent Document 2, International Publication No. 2007/085652 Pamphlet; Patent Document 3).

In addition, it is reported that compounds with a central skeleton of bianthracene, binaphthalene, or a combination of naphthalene and anthracene can be used as materials for organic electroluminescent devices (for example, materials for electron transport layers and electron injection layers; electron transport materials). (JP-A-8-12600; Patent Document 4, JP-A-2003-123983; Patent Document 5, JP-A-11-297473; Patent Document 6).

Furthermore, it has been reported that a compound containing a carbazole ring and a pyridine ring or a pyrimidine ring is used as a charge transport (hole transport property and electron transport property) material (Japanese Patent Laid-Open No. 2006-199679; JP 2005-268199 A; Patent Document 8, JP 2007-088433 A; Patent Document 9, International Publication No. 2003/078541 Pamphlet; Patent Document 10, International Publication No. 2003/080760 Pamphlet;

JP 2003-146951 A JP 2005-170911 A International Publication No. 2007/086552 Pamphlet JP-A-8-12600 JP 2003-123983 A Japanese Patent Laid-Open No. 11-297473 JP 2006-199679 A JP 2005-268199 A JP 2007-088433 A International Publication No. 2003/078541 Pamphlet International Publication No. 2003/080760 Pamphlet

As described above, compounds in which the central skeleton of anthracene is substituted with an aryl group or heteroaryl, compounds using bianthracene, binaphthalene, or a combination of naphthalene and anthracene as the central skeleton, and carbazole rings, pyridine rings, and pyrimidine rings Although several compounds are known, these known materials do not satisfy the long life and high efficiency of the device, which are generally required for electron transport materials, in a sufficient and balanced manner. Under such circumstances, it is desired to develop an electron transport material that has an excellent lifetime and driving voltage of the light emitting element. In particular, for blue light-emitting elements, an electron transport material having superior characteristics compared to red and green light-emitting elements has not been obtained, and development of an electron transport material suitable for improving the characteristics of blue light-emitting elements is desired. ing.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have made an organic electroluminescent device comprising an organic layer containing a compound represented by the following formula (1) as an electron transporting material, in particular, the device. The present inventors have found that an organic electroluminescent device having an excellent lifetime and a well-balanced driving voltage can be obtained. That is, the present invention provides the following carbazole compounds.

[1] A carbazole compound represented by the following formula (1-1).

In the above formula (1-1),
R is aryl having 6 to 24 carbons or heteroaryl having 2 to 24 carbons, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons;
Hy ₁ and Hy ₂ are each independently an electron-accepting nitrogen-containing heteroaryl having 2 to 24 carbon atoms, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. Yes,
Ar ₁ and Ar ₂ are each independently aryl having 6 to 24 carbon atoms which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons;
At least one hydrogen atom in the carbazole compound represented by the formula (1-1) may be substituted with deuterium.

[2] R is phenyl, biphenylyl, terphenylyl, quaterphenyl, naphthyl, phenyl-substituted naphthyl, phenanthrolinyl optionally substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons , Pyridyl, bipyridyl, terpyridyl, quinolinyl, isoquinolinyl, pyrimidinyl, pyrazinyl, pyridazinyl and triazinyl,
Hy ₁ and Hy ₂ are each independently pyridyl, bipyridyl, terpyridyl, pyrimidinyl, pyrazinyl, triazinyl, azaind, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. Lydinyl, benzoimidazolyl, benzothiazolyl, benzoxazolyl, indazolyl, purinyl, carbolinyl, naphthyridinyl, quinoxalinyl, quinolinyl, isoquinolinyl, pyridylquinolinyl, pyridylisoquinolinyl, acridinyl, phenanthrolinyl, phenazinyl and imidazopyridinyl A group selected from the group consisting of:
Ar ₁ and Ar ₂ are each independently benzene, naphthalene, anthracene, naphthacene, pentacene, biphenyl, acenaphthylene, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons, A divalent group having a structure selected from the group consisting of fluorene, phenalene, phenanthrene, triphenylene, pyrene and perylene,
The carbazole compound described in [1] above.

[3] R is phenyl, biphenylyl, terphenylyl, quaterphenyl, naphthyl, phenyl-substituted naphthyl, phenanthrolinyl optionally substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons , A group selected from the group consisting of pyridyl, quinolinyl and isoquinolinyl,
Hy ₁ and Hy ₂ are each independently pyridyl, bipyridyl, terpyridyl, pyrimidinyl, pyrazinyl, triazinyl, azaind, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group selected from the group consisting of lysinyl, benzimidazolyl, benzothiazolyl, benzoxazolyl, quinolinyl, isoquinolinyl, pyridylquinolinyl, pyridylisoquinolinyl and imidazopyridinyl;
Ar ₁ and Ar ₂ are each independently benzene, naphthalene, anthracene, pyrene, triphenylene, fluorene, biphenyl, which may be substituted with alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 6 carbon atoms, and A divalent group of a structure selected from the group consisting of perylene,
The carbazole compound described in [1] above.

[4] R is a group represented by the following formulas (R-1) to (R-20), which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group selected from the group consisting of

Hy ₁ and Hy ₂ are each independently groups represented by the following formulas (Hy-1-1) to (Hy-1-3), and the following formulas (Hy-2-1) to (Hy-2-). 18) a group selected from the group consisting of groups represented by the following formulas (Hy-3-1) to (Hy-3-27):

Ar ₁ and Ar ₂ each independently represents a divalent structure selected from the group consisting of benzene and naphthalene, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons Which is the basis of
The carbazole compound described in [1] above.

[5] R is a group represented by the above formulas (R-1) to (R-14), which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group selected from the group consisting of
Hy ₁ and Hy ₂ are each independently groups represented by the above formulas (Hy-1-1) to (Hy-1-3), and the above formulas (Hy-2-1) to (Hy-2-). 18) a group selected from the group consisting of groups represented by:
Ar ₁ and Ar ₂ are each independently 1,2-phenylene, 1,3-phenylene, 1,4-phenylene, 1,4-naphthalene-diyl, 1,5-naphthalene-diyl, 2,6- A divalent group selected from the group consisting of naphthalene-diyl and 2,7-naphthalene-diyl,
The carbazole compound described in [1] above.

[6] The carbazole compound according to [5], wherein Hy ₁ and Hy ₂ are the same, and Ar ₁ and Ar ₂ are the same.

[7] The carbazole compound according to the above [1], represented by the following formula (1-1-856).

[8] The following formula (1-1-854), formula (1-1-855), formula (1-1-851), formula (1-1-852), formula (1-1-853), formula (1-1-1198), formula (1-1-1220), formula (1-1-98), formula (1-1-99) or formula (1-1-1455), 1].

[9] An electron transport material containing the compound described in any one of [1] to [8] above.

[10] A pair of electrodes including an anode and a cathode, a light emitting layer disposed between the pair of electrodes, an electron transport material according to the above [9] disposed between the cathode and the light emitting layer. An organic electroluminescent device having an electron transport layer and / or an electron injection layer.

[11] At least one of the electron transport layer and the electron injection layer further includes at least one selected from the group consisting of a quinolinol-based metal complex, a pyridine derivative, a bipyridine derivative, a phenanthroline derivative, a borane derivative, and a benzimidazole derivative. The organic electroluminescent element as described in [10] above.

[12] At least one of the electron transport layer and the electron injection layer further includes an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal oxide, an alkali metal halide, an alkaline earth metal oxide, At least one selected from the group consisting of alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes The organic electroluminescent element as described in [11] above.

[13] A display device comprising the organic electroluminescent element according to any one of [10] to [12].

[14] An illumination device including the organic electroluminescent element according to any one of [10] to [12].

According to a preferred embodiment of the present invention, an organic electroluminescent element excellent in the lifetime of the light emitting element can be obtained. In addition, according to another preferable aspect of the present invention, not only an excellent element lifetime can be realized, but also the balance with the driving voltage can be made excellent. Further, the preferred electron transport material of the present invention is particularly suitable for a blue light emitting element, and according to this electron transport material, a blue light emitting element having an element life comparable to a red or green light emitting element can be produced. Can do. Furthermore, by using this organic electroluminescent element, a high-performance display device such as a full-color display can be obtained.

It is a schematic sectional drawing which shows the organic electroluminescent element which concerns on this embodiment.

1. Carbazole Compound Represented by Formula (1) The carbazole compound having a substituent containing an electron-accepting nitrogen-containing heteroaryl according to the present invention will be described in detail. The carbazole compound of the present invention is a compound represented by the following formula (1).

In the formula (1), a is 0 or 1, b is 0 or 1, and there are four structures represented by the following formulas (1-1) to (1-4) depending on the combination of a and b. Among these, in the present application, an embodiment in which a = 1 and b = 1, that is, a compound represented by the above formula (1-1) is particularly preferable.

In the formula (1), R is aryl having 6 to 24 carbon atoms or heteroaryl having 2 to 24 carbon atoms. Hy ₁ and Hy ₂ are each independently an electron-accepting nitrogen-containing heteroaryl having 2 to 24 carbon atoms, and may be the same or different. Furthermore, Ar ₁ and Ar ₂ are each independently arylene having 6 to 24 carbon atoms, but when b = 0, Ar ₂ is aryl having 6 to 24 carbon atoms.

R, Hy ₁ , Hy ₂ , Ar ₁ and Ar ₂ may each independently be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. Examples of the alkyl having 1 to 6 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, n-hexyl, Examples thereof include 1-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl and 2-ethylbutyl. Among these, methyl, isopropyl or t-butyl is preferable, and t-butyl is particularly preferable. Examples of the cycloalkyl having 3 to 6 carbon atoms include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, methylcyclopentyl, cycloheptyl, methylcyclohexyl, cyclooctyl and dimethylcyclohexyl. The number of substituents is, for example, the maximum possible number of substitution, preferably 1 to 3, more preferably 1 to 2, and still more preferably 1.

The “aryl having 6 to 24 carbon atoms” in R is preferably an aryl having 6 to 16 carbon atoms, and more preferably an aryl having 6 to 12 carbon atoms.

Specific examples of “aryl” include monocyclic aryl phenyl, bicyclic aryl (2-, 3-, 4-) biphenylyl, condensed bicyclic aryl (1-, 2-) naphthyl. Terphenylyl which is a tricyclic aryl (m-terphenyl-2'-yl, m-terphenyl-4'-yl, m-terphenyl-5'-yl, o-terphenyl-3'-yl, o -Terphenyl-4'-yl, p-terphenyl-2'-yl, m-terphenyl-2-yl, m-terphenyl-3-yl, m-terphenyl-4-yl, o-terphenyl -2-yl, o-terphenyl-3-yl, o-terphenyl-4-yl, p-terphenyl-2-yl, p-terphenyl-3-yl, p-terphenyl-4-yl) Asena, which is a fused tricyclic aryl Tylene- (1-, 3-, 4-, 5-) yl, fluorene- (1-, 2-, 3-, 4-, 9-) yl, phenalen- (1-, 2-) yl, (1 -, 2-, 3-, 4-, 9-) phenanthryl, quaterphenylyl which is a tetracyclic aryl (5'-phenyl-m-terphenyl-2-yl, 5'-phenyl-m-terphenyl) -3-yl, 5′-phenyl-m-terphenyl-4-yl, m-quaterphenyl), condensed tetracyclic aryl triphenylene- (1-, 2-) yl, pyrene- (1-, 2-, 4-) yl, naphthacene- (1-, 2-, 5-) yl, condensed pentacyclic aryl perylene- (1-, 2-, 3-) yl, pentacene- (1-, 2) -, 5-, 6-) yl and the like. Moreover, the group etc. which the phenyl group substituted by the arbitrary positions of condensed ring system aryl are mention | raise | lifted. The number of substituents is, for example, the maximum possible number of substitution, preferably 1 to 3, more preferably 1 to 2, and still more preferably 1. Among these, phenyl, biphenylyl, terphenylyl, naphthyl, phenanthryl, phenylnaphthyl and those substituted with alkyl having 1 to 6 carbon atoms or cyclohexyl having 3 to 6 carbon atoms are preferable.

The “heteroaryl having 2 to 24 carbon atoms” in R is preferably a heteroaryl having 2 to 20 carbon atoms, more preferably a heteroaryl having 2 to 15 carbon atoms, and particularly preferably 2 to 10 carbon atoms. Of heteroaryl. Examples of the “heteroaryl” include a heterocyclic group containing 1 to 5 heteroatoms selected from oxygen, sulfur and nitrogen in addition to carbon as a ring constituent atom.

Examples of “heteroaryl” include furyl, thienyl, pyrrolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, triazolyl, tetrazolyl, pyrazolyl, pyridyl, pyrimidinyl, pyridazinyl, pyrazinyl, triazinyl, indolyl, isoindolyl, 1H -Indazolyl, benzimidazolyl, benzoxazolyl, benzothiazolyl, 1H-benzotriazolyl, quinolinyl, isoquinolinyl, cinnolyl, quinazolyl, quinoxalinyl, phthalazinyl, naphthyridinyl, purinyl, pteridinyl, carbazolyl, acridinyl, phenoxazinyl, phenothiazinyl, phenothiazinyl, phenothiazinyl Frazanyl, benzofuranyl, isobenzof Sulfonyl, benzo [b] thienyl, phenoxathiinyl, etc. thianthrenyl and the like. Among these, pyridyl, quinolinyl, isoquinolinyl and the like are preferable.

Particularly preferred examples of R include groups represented by the following formulas (R-1) to (R-20). Of these, groups represented by the following formulas (R-1) to (R-14), and groups represented by the following formulas (R-1) to (R-9) are particularly preferable. .

Hy ₁ and Hy ₂ are each independently an electron-accepting nitrogen-containing heteroaryl, and the electron-accepting nitrogen represents a nitrogen atom that forms a double bond with an adjacent atom.

Examples of the electron-accepting nitrogen-containing heteroaryl include pyridyl, bipyridyl, terpyridyl, pyrimidinyl, pyrazinyl, triazinyl, azaindolidinyl, benzimidazolyl, benzothiazolyl, benzoxazolyl, indazolyl, purinyl, carbolinyl, naphthyridinyl, quinoxalinyl, quinolinyl, isoquinolinyl, Examples include pyridylquinolinyl, pyridylisoquinolinyl, acridinyl, phenanthrolinyl, phenazinyl and imidazopyridinyl. Among them, preferred are pyridyl, bipyridyl, terpyridyl, pyrimidinyl, pyrazinyl, triazinyl, azaindolizinyl, benzimidazolyl, benzothiazolyl, benzoxazolyl, quinolinyl, isoquinolinyl, pyridylquinolinyl, pyridylisoquinolinyl and imidazopyridinyl. Particularly preferred are pyridyl and bipyridyl.

Among the above, Hy ₁ or Hy ₂ is preferably a group represented by the following formulas (Hy-1-1) to (Hy-1-3), or the following formulas (Hy-2-1) to (Hy-2-). 18), and groups represented by the following formulas (Hy-3-1) to (Hy-3-27).

More preferred as Hy ₁ or Hy ₂ are groups represented by the above formulas (Hy-1-1) to (Hy-1-3), and the above formulas (Hy-2-1) to (Hy-2-18). It is group represented by these.

Ar ₁ and Ar ₂ are each independently an arylene having 6 to 24 carbon atoms, but when b = 0 (when there is no Hy ₂ group), Ar ₂ is an aryl having 6 to 24 carbon atoms.

As the arylene, a divalent group derived from an aromatic hydrocarbon group such as benzene, naphthalene, anthracene, naphthacene, pentacene, acenaphthylene, phenalene, phenanthrene, pyrene, triphenylene, fluorene, biphenyl, and perylene can be used. A divalent group derived from naphthalene is preferred.

Divalent groups derived from benzene or naphthalene include 1,2-phenylene, 1,3-phenylene, 1,4-phenylene, 1,4-naphthalene-diyl, 1,5-naphthalene-diyl, 2,6- And naphthalene-diyl and 2,7-naphthalene-diyl.

When b = 0, the specific aryl of Ar ₂ includes the groups exemplified in the above description of R, and the groups represented by the above formulas (R-1) to (R-9) are preferable. Particularly preferred are groups represented by the above formula (R-1), formula (R-6) and formula (R-7).

In particular, in the case of the structure represented by the above formula (1-1), Hy ₁ and Hy ₂ may be the same or different, but are preferably the same, and Ar ₁ and Ar ₂ are also the same. Or may be different, but preferably the same.

In addition, all or part of the hydrogen atoms in carbazole and R, Ar ₁ , Ar ₂ , Hy ₁ or Hy ₂ substituted for carbazole, which constitute the compound represented by the above formula (1), are deuterium. There may be.

Specific examples of the compound represented by the above formula (1) include, for example, the following formulas (1-1-1) to (1-1-1458) belonging to the compound represented by the above formula (1-1). ), Compounds represented by the following formulas (1-2-1) to (1-2-629) belonging to the compounds represented by the above formula (1-2), the above formula (1) -3) belonging to the compound represented by the following formulas (1-3-1) to (1-3-924), belonging to the compound represented by the above formula (1-4), Examples thereof include compounds represented by the following formulas (1-4-1) to (1-4-561).

Among the compounds represented by the above formulas (1-1-1) to (1-1-1458), among these, the above formulas (1-1-1) to (1-1-9), 1-1-13) to Formula (1-1-18), Formula (1-1-25) to Formula (1-1-27), Formula (1-1-31) to Formula (1-1-36) ), Formula (1-1-97) to Formula (1-1-102), Formula (1-1-106) to Formula (1-1-111), Formula (1-1-289) to Formula (1) -293), Formula (1-1-332) to Formula (1-1-334), Formula (1-1-375) to Formula (1-1-378), Formula (1-1-417) Formula (1-1-419), Formula (1-1-462) to Formula (1-1-464), Formula (1-1-514) to Formula (1-1-516), Formula (1- 1-559), formula (1-1-560), formula (1-1-599) to formula 1-1-601), formula (1-1-644), formula (1-1-683) to formula (1-1-685), formula (1-1-826), formula (1-1-827) ), Formula (1-1-836), Formula (1-1-851) to Formula (1-1-859), Formula (1-1-863) to Formula (1-1-868), Formula (1) -1-875) to formula (1-1-877), formula (1-1-881) to formula (1-1-886), formula (1-1-943) to formula (1-1-948) Formula (1-1-987) to Formula (1-1-993), Formula (1-1-1032) to Formula (1-1-1034), Formula (1-1-1036) to Formula (1- 1-1038), Formula (1-1-1076) to Formula (1-1-1087), Formula (1-1-1091) to Formula (1-1-1096), Formula (1-11-1103) to Formula (1-1-1105), Formula (1-1 1109) to Formula (1-11-1114), Formula (1-1-1171) to Formula (1-1-1175), Formula (1-1-1178) to Formula (1-1-1184), Formula ( 1-1-1187) to formula (1-1-1195), formula (1-11-1198) to formula (1-1-1206), formula (1-1-1210) to formula (1-1-1215) ), Formula (1-11-222) to formula (1-1-1224), formula (1-1-1228) to formula (1-1-1233), formula (1-1-1290) to formula (1) -1-1294), formula (1-1-1297) to formula (1-1-1303), formula (1-1-1306) to formula (1-1-1314), formula (1-1-1317) Formula (1-1-1325), Formula (1-1-1329) to Formula (1-1-1334), Formula (1-1-1341) to Formula (1-1-1343), Formula (1) -1-1347) to Formula (1-1-1349), Formula (1-11409) to Formula (1-1-1413), Formula (1-1-1416) to Formula (1-1-1422) , Formula (1-1-1425) to Formula (1-1-1433), Formula (1-1-1438) to Formula (1-1-1440), and Formula (1-1-1448) to Formula (1- 1-1456) is preferred. Further, the above formula (1-1-1) to formula (1-1-6), formula (1-1-97) to formula (1-1-99), formula (1-1-559), formula ( 1-1-560), formula (1-1-851) to formula (1-1-856), formula (1-1-1198) to formula (1-1-1203), formula (1-1-1317) ) To formula (1-11322), formula (1-1-1448) to formula (1-1-1450) and formula (1-1-1454) to formula (1-1-1456). Compounds are more preferred.

2. Method for Producing Compound Represented by Formula (1) Next, the method for producing the carbazole compound of the present invention will be described.
The carbazole compound of the present invention basically comprises a known compound and a known synthesis method such as Suzuki coupling reaction or Negishi coupling reaction (for example, “Metal-Catalyzed Cross-Coupling Reactions—Second, Completely Revised”). and Enlarged Edition ”). It can also be synthesized by combining both reactions. A scheme for synthesizing the carbazole compound represented by the formula (1) by Suzuki coupling reaction or Negishi coupling reaction is illustrated below.

<Method for Synthesizing Carbazole Compound Represented by Formula (1) (Part 1)>
<Synthesis of carbazole-2,7-diyl bis (trifluoromethanesulfonate) substituted with R at N-position: Cz-R-OTf>
As shown in the following reaction formula (1), a compound represented by “Cz-H-OMe” obtained by using a known synthesis method (Macromolecules, vol.35, pp.2122-2128 (2002)) After introducing a substituent R by a coupling reaction using a palladium catalyst, an Ullmann reaction, or a nucleophilic substitution reaction using cesium carbonate to obtain a compound represented by “Cz—R—OMe”, tribromide A compound represented by “Cz—R—OH” is synthesized by demethylation with boron or pyridine hydrochloride. Thereafter, a compound represented by “Cz—R—OTf” is obtained by reacting with trifluoromethanesulfonic anhydride.

<Carbazole-2,7-dibromo substituted with R at N-position): Synthesis of Cz-R-Br>
As shown in the following reaction formula (2), a known synthesis method (Chemistry of Materials, vol.16, pp.4736-4742 (2004), Journal of Organic Chemistry, vol.70, pp.5014-5019 (2005) The substituent R is introduced into the compound represented by “Cz—H—Br” obtained by using a coupling reaction using a palladium catalyst, an Ullmann reaction, or a nucleophilic substitution reaction using cesium carbonate. A compound represented by “Cz—R—Br” is obtained.

<Carbazole-2,7-diboronic acid ester substituted with R at N-position: Synthesis of Cz-R-BPin>
As shown in the following reaction formula (3), the compound represented by “Cz—R—OTf” or “Cz—R—Br” obtained as described above, and bis (pinacolato) diboron or 4,4 , 5,5-tetramethyl-1,3,2-dioxaborolane can be synthesized by a coupling reaction using a palladium catalyst and a base to synthesize a compound represented by “Cz-R-BPin”. .

<Synthesis of Carbazole Compound According to the Present Invention>
Finally, as shown in the following reaction formulas (4) to (6), the compound represented by “Cz-R-OTf” or “Cz-R-BPin” obtained as described above and the reactivity By reacting “Hy _1- (Ar ₁ ) _a ” and “(Hy ₂ ) _b —Ar ₂ ” having a substituent of the following by Suzuki coupling or Negishi coupling, the carbazole represented by the formula (1) A compound can be obtained. Here, “Hy _1- (Ar ₁ ) _a ” and “(Hy ₂ ) _b —Ar ₂ ” mean groups bonded to the 2nd and 7th positions of the carbazole skeleton of the compound represented by the formula (1). , A and b are 0 or 1.

Here, Hy ₁ and Hy ₂ are each independently an optionally substituted electron-accepting nitrogen-containing heteroaryl having 2 to 24 carbon atoms, which may be the same or different, and Ar ₁ and Ar ₂ are each independently an arylene having 6 to 24 carbon atoms which may be substituted. However, when b = 0, Ar ₂ is an optionally substituted aryl having 6 to 24 carbon atoms.

Here, when “Hy _1- (Ar ₁ ) _a ” and “(Hy ₂ ) _b —Ar ₂ ” represent the same group, an electron obtained by bonding a reactive substituent to these groups The carbazole compound according to the present invention can be synthesized by using 2-fold moles of the accepting nitrogen-containing heteroaryl derivative. In addition, when “Hy _1- (Ar ₁ ) _a ” and “(Hy ₂ ) _b —Ar ₂ ” represent different groups, the respective electron acceptors in which reactive substituents are bonded to these groups. The carbazole derivative according to the present invention can be synthesized by reacting the functional nitrogen-containing heteroaryl derivative at the same time or in steps of 1 mole.

<Reagent used in reaction>
Specific examples of the palladium catalyst used in the Suzuki coupling reaction include tetrakis (triphenylphosphine) palladium (0): Pd (PPh ₃ ) ₄ , bis (triphenylphosphine) palladium (II) dichloride: PdCl ₂ (PPh ₃ ) ₂ , palladium (II) acetate: Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0): Pd ₂ (dba) ₃ , tris (dibenzylideneacetone) dipalladium (0) chloroform complex: Pd ₂ (Dba) ₃ · CHCl ₃ , bis (dibenzylideneacetone) palladium (0): Pd (dba) ₂ , PdCl ₂ {P (t-Bu) _2- (p-NMe ₂ -Ph)} ₂ , palladium bis ( Dibenzylidene).

In order to promote the reaction, a phosphine compound may be added to these palladium compounds in some cases. Specific examples of the phosphine compound include tri (t-butyl) phosphine, tricyclohexylphosphine, 1- (N, N-dimethylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (N, N-dibutylaminomethyl) -2- (di-t-butylphosphino) ferrocene, 1- (methoxymethyl) -2- (di-t-butylphosphino) ferrocene, 1,1′-bis (di-t-butylphos Fino) ferrocene, 2,2′-bis (di-t-butylphosphino) -1,1′-binaphthyl, 2-methoxy-2 ′-(di-t-butylphosphino) -1,1′-binaphthyl, or 2-dicyclohexylphosphino-2 ', 6'-dimethoxybiphenyl.

Specific examples of bases used in the Suzuki coupling reaction include sodium carbonate, potassium carbonate, cesium carbonate, sodium bicarbonate, sodium hydroxide, potassium hydroxide, barium hydroxide, sodium ethoxide, sodium t-butoxide, sodium acetate. , Tripotassium phosphate, or potassium fluoride.

Specific examples of the solvent used in the Suzuki coupling reaction include benzene, toluene, xylene, 1,2,4-trimethylbenzene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butyl methyl ether, 1 1,4-dioxane, methanol, ethanol, cyclopentyl methyl ether or isopropyl alcohol. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

Specific examples of the palladium catalyst used in the Negishi coupling reaction include tetrakis (triphenylphosphine) palladium (0): Pd (PPh ₃ ) ₄ , bis (triphenylphosphine) palladium (II) dichloride: PdCl ₂ (PPh ₃ ) ₂ , palladium (II) acetate: Pd (OAc) ₂ , tris (dibenzylideneacetone) dipalladium (0): Pd ₂ (dba) ₃ , tris (dibenzylideneacetone) dipalladium (0) chloroform complex: Pd ₂ (Dba) ₃ · CHCl ₃ , bis (dibenzylideneacetone) palladium (0): Pd (dba) ₂ , bis (tri-t-butylphosphino) palladium (0), or (1,1′-bis (diphenylphosphine) Fino) ferrocene) dichloropalladium (II): Pd (dpp ) Cl _2, and the like.

Specific examples of the solvent used in the Negishi coupling reaction include benzene, toluene, xylene, 1,2,4-trimethylbenzene, N, N-dimethylformamide, tetrahydrofuran, diethyl ether, t-butyl methyl ether, cyclopentyl. Examples include methyl ether or 1,4-dioxane. These solvents can be appropriately selected and may be used alone or as a mixed solvent.

<Synthesis of groups bonded to positions 2 and 7 of the carbazole skeleton of the compound represented by formula (1)>
“Hy _1- (Ar ₁ ) _a ” and “(Hy ₂ ) _b —Ar ₂ ” having a reactive substituent bonded thereto can be obtained by combining known reactions. The case where Hy ₁ and Hy ₂ are pyridyl groups and Ar ₁ and Ar ₂ are phenylene or naphthalenylene is shown.

<Synthesis of pyridyl-substituted bromophenyl / bromonaphthyl>
First, a zinc chloride complex of pyridine is synthesized as shown in the following reaction formula (7), and then a zinc chloride complex of pyridine and 1,4-dibromobenzene or 1,4-dibromo as shown in the following reaction formula (8). 2- (4-bromophenyl) pyridine or 2- (4-bromonaphthalen-1-yl) pyridine can be synthesized by reacting with naphthalene.

In the reaction formula (7), “ZnCl ₂ · TMEDA” is a tetramethylethylenediamine complex of zinc chloride. R represents a linear or branched alkyl group, preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

Here, the synthesis method of 2- (4-bromophenyl) pyridine and 2- (4-bromonaphthalen-1-yl) pyridine using 2-bromopyridine as a raw material is exemplified, but 3-bromopyridine or 4 By using -bromopyridine and by using iodopyridine, the corresponding objects, ie 3- (4-bromophenyl) pyridine (or 3- (4-bromonaphthalen-1-yl) pyridine) and 4 respectively -(4-Bromophenyl) pyridine (or 4- (4-bromonaphthalen-1-yl) pyridine) can be obtained. Also illustrated here is a method for synthesizing 2- (4-bromophenyl) pyridine and 2- (4-bromonaphthalen-1-yl) pyridine using 1,4-dibromobenzene or 1,4-dibromonaphthalene as raw materials. However, by using 1,3-dibromobenzene, 2,6-dibromonaphthalene or 2,7-dibromonaphthalene as a raw material, dichloro, diiodo, bis (trifluoromethanesulfonate) By using a mixture of them (for example: 1-bromo-4-iodobenzene, etc.), the corresponding target product, ie, 2- (3-bromophenyl) pyridine, 2- (6-bromonaphthalen-2-yl) ) Pyridine and 2- (7-bromonaphthalen-2-yl) pyridine can be obtained. Kill.

Further, instead of reacting 1,4-dibromobenzene or the like with a zinc chloride complex of pyridine, a similar target product can be obtained by reacting pyridylboronic acid or pyridylboronic acid ester (coupling reaction).

<Synthesis of pyridyl-substituted phenyl / naphthylboronic acid and boronate ester>
Next, as shown in the following reaction formula (9), 2- (4-bromophenyl) pyridine or 2- (4-bromonaphthalen-1-yl) pyridine is lithiated using an organolithium reagent, By using magnesium or an organomagnesium reagent as a Grignard reagent and reacting with trimethyl borate, triethyl borate or triisopropyl borate, 4- (pyridin-2-yl) phenylboronic acid ester and 4- (pyridine- 2-yl) naphthalen-1-ylboronic acid esters can be synthesized. Further, as shown in the following reaction formula (10), 4- (2-pyridyl) phenylboronic acid and 4- (pyridin-2-yl) naphthalen-1-ylboronic acid are obtained by hydrolyzing the boronic ester. Can be synthesized.

In the above reaction formula (9), R represents a linear or branched alkyl group, preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

Alternatively, as shown in the following reaction formula (11), 2- (4-bromophenyl) pyridine or 2- (4-bromonaphthalen-1-yl) pyridine may be lithiated using an organolithium reagent, or magnesium Or an organomagnesium reagent to form a Grignard reagent and react with bis (pinacolato) diboron or 4,4,5,5-tetramethyl-1,3,2-dioxaborolane to produce other 4- (pyridine-2- Yl) phenylboronic acid esters and 4- (pyridin-2-yl) naphthalen-1-ylboronic acid esters can be synthesized. Further, as shown in the following reaction formula (12), 2- (4-bromophenyl) pyridine or 2- (4-bromonaphthalen-1-yl) pyridine and bis (pinacolato) diboron or 4,4,5, The same 4- (pyridin-2-yl) phenylboronic acid ester and 4- (pyridine) can also be obtained by coupling reaction of 5-tetramethyl-1,3,2-dioxaborolane with a palladium catalyst and a base. -2-yl) naphthalen-1-ylboronic acid ester can be synthesized.

In the above reaction formula (11), R represents a linear or branched alkyl group, preferably a linear or branched alkyl group having 1 to 4 carbon atoms.

In the above reaction formula (9), (11) or (12), 3- (4-bromophenyl) pyridine, 4- (4-bromophenyl) pyridine, 2- (3-bromophenyl) pyridine, 3- (3-bromophenyl) pyridine, 4- (3-bromophenyl) pyridine, 3- (4-bromonaphthalen-1-yl) pyridine, 4- (4-bromonaphthalen-1-yl) pyridine, 2- (4 -Bromonaphthalen-1-yl) pyridine, 4- (4-bromonaphthalen-1-yl) pyridine, 2- (6-bromonaphthalen-2-yl) pyridine, 3- (6-bromonaphthalen-2-yl) Pyridine, 4- (6-bromonaphthalen-2-yl) pyridine, 2- (7-bromonaphthalen-2-yl) pyridine, 3- (7-bromonaphthalen-2-yl) pyrid , It can be synthesized corresponding boronic acid / boronate esters with 4- (7-bromo-2-yl) regioisomer like pyridine.

Further, in the above reaction formula (9), (11) or (12), instead of bromides such as 2- (4-bromophenyl) pyridine and 3- (4-bromonaphthalen-1-yl) pyridine, A compound can be synthesized in the same manner using a compound, iodide or trifluoromethanesulfonate.

<Method for Synthesizing Carbazole Compound Represented by Formula (1) (Part 2)>
The carbazole compound of the present invention has a “Hy _1- (Ar ₁ ) _a —” group and a “(Hy ₂ ) _b —Ar ₂ —” group at the 2nd and 7th positions of the carbazole skeleton as described above. In addition to the method of bonding by, for example, “Ar ₁ (or Ar ₂ )” and “Hy ₁ (or Hy ₂ )” may be bonded in order to the carbazole skeleton as follows.

<Synthesis of carbazole-2,7-diyl bis (trifluoromethanesulfonate) substituted with R at N-position: Cz-R-ArOTf>
As shown in the following reaction formula (13), a compound represented by “Cz—H—Br” is bonded to an alkoxyaryl (for example, R = methoxy group or ethoxy group, Ar = phenyl or The compound represented by “Cz—H—ArOR” is reacted with a boronic acid of naphthyl) and then subjected to a coupling reaction using a palladium catalyst, an Ullmann reaction, or a nucleophilic substitution reaction using cesium carbonate. Cz-R-ArOR "is synthesized. Next, demethylation is performed using boron tribromide, pyridine hydrochloride, or the like to synthesize a compound represented by “Cz—R—ArOH”. Thereafter, a compound represented by “Cz—R—ArOTf” is obtained by reacting with trifluoromethanesulfonic anhydride. In the reaction formula (13), R which is an alkyl part of alkoxy and R which is a substituent bonded to the 9-position of carbazole are represented by the same symbol, but they may be the same or different.

<Synthesis of Carbazole Compound According to the Present Invention>
As shown in the following reaction formula (14) or reaction formula (15), the compound represented by “Cz—R—ArOTf” obtained as described above and “Hy ₁ ” having a reactive substituent. And by reacting “Hy ₂ ” with Suzuki coupling or Negishi coupling, the carbazole compound represented by the formula (1) can be obtained. Further, as shown in the following reaction formula (16), after the triflate is converted into a boronic acid ester using a Pd catalyst, this is converted into a halide or triflate of “Hy ₁ ” and “Hy ₂ ” with a Suzuki coupling reaction. The carbazole compound represented by the formula (1) can also be obtained by coupling them.

The synthesis method according to the above reaction formulas (13) to (16) is optimal for the synthesis of a carbazole compound in which Hy ₁ and Hy ₂ may be the same or different, but Ar ₁ and Ar ₂ are the same. is there.

In addition, the compounds of the present invention include those in which at least a part of the hydrogen atoms are substituted with deuterium. Such a compound can be obtained by using a raw material in which a desired position is deuterated. It can be synthesized in the same way.

3. Organic Electroluminescent Device The carbazole compound according to the present invention can be used as a material for an organic electroluminescent device, for example. Below, the organic electroluminescent element which concerns on this embodiment is demonstrated in detail based on drawing. FIG. 1 is a schematic cross-sectional view showing an organic electroluminescent element according to this embodiment.

<Structure of organic electroluminescence device>
An organic electroluminescent device 100 shown in FIG. 1 includes a substrate 101, an anode 102 provided on the substrate 101, a hole injection layer 103 provided on the anode 102, and a hole injection layer 103. A hole transport layer 104 provided on the light emitting layer 105, a light emitting layer 105 provided on the hole transport layer 104, an electron transport layer 106 provided on the light emitting layer 105, and an electron transport layer 106. And the cathode 108 provided on the electron injection layer 107.

The organic electroluminescent element 100 is manufactured in the reverse order, for example, the substrate 101, the cathode 108 provided on the substrate 101, the electron injection layer 107 provided on the cathode 108, and the electron injection layer. An electron transport layer 106 provided on 107, a light-emitting layer 105 provided on the electron transport layer 106, a hole transport layer 104 provided on the light-emitting layer 105, and a hole transport layer 104 A structure including the hole injection layer 103 provided above and the anode 102 provided on the hole injection layer 103 may be employed.

Not all of the above-described layers are necessary, and the minimum structural unit is composed of the anode 102, the light emitting layer 105, the electron transport layer 106 and / or the electron injection layer 107 and the cathode 108. The hole transport layer 104 is an arbitrarily provided layer. Moreover, each said layer may consist of a single layer, respectively, and may consist of multiple layers.

As an aspect of the layer constituting the organic electroluminescence device, in addition to the above-described configuration aspect of “substrate / anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode”, "Substrate / anode / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode", "substrate / anode / hole injection layer / light emitting layer / electron transport layer / electron injection layer / cathode", "substrate / Anode / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode ”,“ substrate / anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / cathode ”,“ substrate ” / Anode / light emitting layer / electron transport layer / electron injection layer / cathode ”,“ substrate / anode / hole transport layer / light emitting layer / electron injection layer / cathode ”,“ substrate / anode / hole transport layer / light emitting layer / “Electron transport layer / cathode”, “substrate / anode / hole injection layer / light emitting layer / electron injection layer / cathode”, “substrate / anode / hole injection layer / light emitting layer / electron” Okuso / cathode "," substrate / anode / light emitting layer / electron transporting layer / cathode "may be configured aspect of the" substrate / anode / light emitting layer / electron injection layer / cathode ".

<Substrate in organic electroluminescence device>
The substrate 101 serves as a support for the organic electroluminescent device 100, and usually quartz, glass, metal, plastic, or the like is used. The substrate 101 is formed into a plate shape, a film shape, or a sheet shape according to the purpose. For example, a glass plate, a metal plate, a metal foil, a plastic film, a plastic sheet, or the like is used. Of these, glass plates and transparent synthetic resin plates such as polyester, polymethacrylate, polycarbonate, polysulfone and the like are preferable. In the case of a glass substrate, soda lime glass, non-alkali glass, or the like is used, and the thickness only needs to be sufficient to maintain the mechanical strength. The upper limit value of the thickness is, for example, 2 mm or less, preferably 1 mm or less. The glass material is preferably alkali-free glass because it is better to have less ions eluted from the glass. However, soda lime glass with a barrier coat such as SiO ₂ is also commercially available, so it can be used. it can. Further, the substrate 101 may be provided with a gas barrier film such as a dense silicon oxide film on at least one surface in order to improve the gas barrier property, and a synthetic resin plate, film or sheet having a low gas barrier property is used as the substrate 101. When used, it is preferable to provide a gas barrier film.

<Anode in organic electroluminescence device>
The anode 102 serves to inject holes into the light emitting layer 105. When the hole injection layer 103 and / or the hole transport layer 104 are provided between the anode 102 and the light emitting layer 105, holes are injected into the light emitting layer 105 through these layers. .

Examples of the material for forming the anode 102 include inorganic compounds and organic compounds. Examples of inorganic compounds include metals (aluminum, gold, silver, nickel, palladium, chromium, etc.), metal oxides (indium oxide, tin oxide, indium-tin oxide (ITO), indium-zinc oxide) Products (IZO), metal halides (copper iodide, etc.), copper sulfide, carbon black, ITO glass, Nesa glass, and the like. Examples of the organic compound include polythiophene such as poly (3-methylthiophene), conductive polymer such as polypyrrole and polyaniline, and the like. In addition, it can select suitably from the substances currently used as an anode of an organic electroluminescent element, and can use it.

The resistance of the transparent electrode is not particularly limited as long as a current sufficient for light emission of the light emitting element can be supplied, but it is desirable that the resistance is low from the viewpoint of power consumption of the light emitting element. For example, an ITO substrate of 300Ω / □ or less functions as an element electrode, but at present, since it is possible to supply a substrate of about 10Ω / □, for example, 100 to 5Ω / □, preferably 50 to 5Ω. It is particularly desirable to use a low resistance product of / □. The thickness of ITO can be arbitrarily selected according to the resistance value, but is usually used in a range of 100 to 300 nm.

<Hole injection layer and hole transport layer in organic electroluminescence device>
The hole injection layer 103 plays a role of efficiently injecting holes moving from the anode 102 into the light emitting layer 105 or the hole transport layer 104. The hole transport layer 104 plays a role of efficiently transporting holes injected from the anode 102 or holes injected from the anode 102 through the hole injection layer 103 to the light emitting layer 105. The hole injection layer 103 and the hole transport layer 104 are each formed by laminating and mixing one kind or two or more kinds of hole injection / transport materials or a mixture of the hole injection / transport material and the polymer binder. Is done. In addition, an inorganic salt such as iron (III) chloride may be added to the hole injection / transport material to form a layer.

As a hole injection / transport material, it is necessary to efficiently inject and transport holes from the positive electrode between electrodes to which an electric field is applied. The hole injection efficiency is high, and the injected holes are transported efficiently. It is desirable to do. For this purpose, it is preferable to use a substance that has a low ionization potential, a high hole mobility, excellent stability, and is less likely to generate trapping impurities during production and use.

As a material for forming the hole injection layer 103 and the hole transport layer 104, in a photoconductive material, a compound conventionally used as a charge transport material for holes, a p-type semiconductor, and a hole injection of an organic electroluminescent element are used. Any known material used for the layer and the hole transport layer can be selected and used. Specific examples thereof include carbazole derivatives (N-phenylcarbazole, polyvinylcarbazole, etc.), biscarbazole derivatives such as bis (N-arylcarbazole) or bis (N-alkylcarbazole), triarylamine derivatives (aromatic tertiary class). Polymer having amino group in main chain or side chain, 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane, N, N′-diphenyl-N, N′-di (3-methylphenyl)- 4,4'-diaminobiphenyl, N, N'-diphenyl-N, N'-dinaphthyl-4,4'-diaminobiphenyl, N, N'-diphenyl-N, N'-di (3-methylphenyl)- 4,4′-diphenyl-1,1′-diamine, N, N′-dinaphthyl-N, N′-diphenyl-4,4′-diphenyl- , 1'-diamine, 4,4 ', 4 "-tris (3-methylphenyl (phenyl) amino) triphenylamine, and other triphenylamine derivatives, starburst amine derivatives, stilbene derivatives, phthalocyanine derivatives (metal-free, Copper phthalocyanine, etc.), pyrazoline derivatives, hydrazone compounds, benzofuran derivatives, thiophene derivatives, heterocyclic compounds such as oxadiazole derivatives, porphyrin derivatives, polysilanes, etc. Styrene derivatives, polyvinyl carbazole, polysilane, and the like are preferable, but there is no particular limitation as long as it is a compound that forms a thin film necessary for manufacturing a light-emitting element, can inject holes from the anode, and can further transport holes. .

It is also known that the conductivity of organic semiconductors is strongly influenced by the doping. Such an organic semiconductor matrix material is composed of a compound having a good electron donating property or a compound having a good electron accepting property. Strong electron acceptors such as tetracyanoquinone dimethane (TCNQ) or 2,3,5,6-tetrafluorotetracyano-1,4-benzoquinone dimethane (F4TCNQ) are known for doping of electron donor materials. (For example, the document “M. Pfeiffer, A. Beyer, T. Fritz, K. Leo, Appl. Phys. Lett., 73 (22), 3202-3204 (1998)”) and the document “J. Blochwitz, M Pheiffer, T. Fritz, K. Leo, Appl. Phys. Lett., 73 (6), 729-731 (1998)). These generate so-called holes by an electron transfer process in an electron donating base material (hole transport material). Depending on the number and mobility of holes, the conductivity of the base material varies considerably. Known matrix substances having hole transporting properties include, for example, benzidine derivatives (TPD and the like), starburst amine derivatives (TDATA and the like), and specific metal phthalocyanines (particularly zinc phthalocyanine ZnPc and the like). 2005-167175).

<Light emitting layer in organic electroluminescent element>
The light emitting layer 105 emits light by recombining holes injected from the anode 102 and electrons injected from the cathode 108 between electrodes to which an electric field is applied. The material for forming the light-emitting layer 105 may be a compound that emits light by being excited by recombination of holes and electrons (a light-emitting compound), can form a stable thin film shape, and is in a solid state It is preferable that the compound exhibits a high emission (fluorescence and / or phosphorescence) efficiency.

The light emitting layer may be either a single layer or a plurality of layers, each formed of a light emitting material (host material, dopant material). Each of the host material and the dopant material may be one kind or a plurality of combinations. The dopant material may be included in the host material as a whole, or may be included partially. As a doping method, it can be formed by a co-evaporation method with a host material, but it may be pre-mixed with the host material and then simultaneously deposited.

∙ The amount of host material used depends on the type of host material and can be determined according to the characteristics of the host material. The amount of the host material used is preferably 50 to 99.999% by weight of the entire light emitting material, more preferably 80 to 99.95% by weight, and still more preferably 90 to 99.9% by weight. .

The amount of dopant material used depends on the type of dopant material, and can be determined according to the characteristics of the dopant material. The standard of the amount of dopant used is preferably 0.001 to 50% by weight of the entire light emitting material, more preferably 0.05 to 20% by weight, and still more preferably 0.1 to 10% by weight. The above range is preferable in that, for example, the concentration quenching phenomenon can be prevented.

The light emitting material of the light emitting device according to this embodiment may be either fluorescent or phosphorescent.

The host material is not particularly limited, but has previously been known as a phosphor, fused ring derivatives such as anthracene and pyrene, metal chelated oxinoid compounds such as tris (8-quinolinolato) aluminum, bis Bisstyryl derivatives such as styryl anthracene derivatives and distyrylbenzene derivatives, tetraphenylbutadiene derivatives, coumarin derivatives, oxadiazole derivatives, pyrrolopyridine derivatives, perinone derivatives, cyclopentadiene derivatives, oxadiazole derivatives, thiadiazolopyridine derivatives, pyrrolopyrrole In derivatives, fluorene derivatives, benzofluorene derivatives, and polymer systems, polyphenylene vinylene derivatives, polyparaphenylene derivatives, and polythiophene derivatives are preferably used.

In addition, as a host material, it can be used by appropriately selecting from compounds described in Chemical Industry, June 2004, page 13, and references cited therein.

Further, the dopant material is not particularly limited, and a known compound can be used, and can be selected from various materials according to a desired emission color. Specifically, for example, condensed ring derivatives such as phenanthrene, anthracene, pyrene, tetracene, pentacene, perylene, naphthopylene, dibenzopyrene, rubrene, and chrysene, benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, benzotriazole derivatives, Bisstyryl such as oxazole derivatives, oxadiazole derivatives, thiazole derivatives, imidazole derivatives, thiadiazole derivatives, triazole derivatives, pyrazoline derivatives, stilbene derivatives, thiophene derivatives, tetraphenylbutadiene derivatives, cyclopentadiene derivatives, bisstyrylanthracene derivatives and distyrylbenzene derivatives Derivatives (Japanese Patent Laid-Open No. 1-245087), bisstyrylarylene derivatives (Japanese Patent Laid-Open No. 2-2472) No. 8), diazaindacene derivatives, furan derivatives, benzofuran derivatives, phenylisobenzofuran, dimesitylisobenzofuran, di (2-methylphenyl) isobenzofuran, di (2-trifluoromethylphenyl) isobenzofuran, phenylisobenzofuran, etc. Isobenzofuran derivatives, dibenzofuran derivatives, 7-dialkylaminocoumarin derivatives, 7-piperidinocoumarin derivatives, 7-hydroxycoumarin derivatives, 7-methoxycoumarin derivatives, 7-acetoxycoumarin derivatives, 3-benzothiazolylcoumarin derivatives, Coumarin derivatives such as 3-benzimidazolylcoumarin derivatives, 3-benzoxazolylcoumarin derivatives, dicyanomethylenepyran derivatives, dicyanomethylenethiopyran derivatives, polymethine derivatives, Anine derivatives, oxobenzoanthracene derivatives, xanthene derivatives, rhodamine derivatives, fluorescein derivatives, pyrylium derivatives, carbostyril derivatives, acridine derivatives, oxazine derivatives, phenylene oxide derivatives, quinacridone derivatives, quinazoline derivatives, pyrrolopyridine derivatives, furopyridine derivatives, 1, Examples include 2,5-thiadiazolopyrene derivatives, pyromethene derivatives, perinone derivatives, pyrrolopyrrole derivatives, squarylium derivatives, violanthrone derivatives, phenazine derivatives, acridone derivatives, deazaflavin derivatives, fluorene derivatives, and benzofluorene derivatives.

Illustratively for each color light, blue to blue-green dopant materials include naphthalene, anthracene, phenanthrene, pyrene, triphenylene, perylene, fluorene, indene, chrysene and other aromatic hydrocarbon compounds and derivatives thereof, furan, pyrrole, thiophene, Aromatic complex such as silole, 9-silafluorene, 9,9'-spirobisilafluorene, benzothiophene, benzofuran, indole, dibenzothiophene, dibenzofuran, imidazopyridine, phenanthroline, pyrazine, naphthyridine, quinoxaline, pyrrolopyridine, thioxanthene Ring compounds and their derivatives, distyrylbenzene derivatives, tetraphenylbutadiene derivatives, stilbene derivatives, aldazine derivatives, coumarin derivatives, imidazole, thiazole, thiadia Azole derivatives such as azole, carbazole, oxazole, oxadiazole, triazole and metal complexes thereof, and N, N′-diphenyl-N, N′-di (3-methylphenyl) -4,4′-diphenyl-1 , 1'-diamine and aromatic amine derivatives.

Examples of the green to yellow dopant material include coumarin derivatives, phthalimide derivatives, naphthalimide derivatives, perinone derivatives, pyrrolopyrrole derivatives, cyclopentadiene derivatives, acridone derivatives, quinacridone derivatives, and naphthacene derivatives such as rubrene. A compound in which a substituent capable of increasing the wavelength such as aryl, heteroaryl, arylvinyl, amino, and cyano is introduced into the compound exemplified as the blue to blue-green dopant material is also a suitable example.

Furthermore, orange to red dopant materials include naphthalimide derivatives such as bis (diisopropylphenyl) perylenetetracarboxylic imide, perinone derivatives, rare earth complexes such as Eu complexes having acetylacetone, benzoylacetone and phenanthroline as ligands, 4 -(Dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran and its analogs, metal phthalocyanine derivatives such as magnesium phthalocyanine and aluminum chlorophthalocyanine, rhodamine compounds, deazaflavin derivatives, coumarin derivatives, quinacridone Derivatives, phenoxazine derivatives, oxazine derivatives, quinazoline derivatives, pyrrolopyridine derivatives, squarylium derivatives, violanthrone derivatives, phenazine derivatives, phenoxazo Derivatives, thiadiazolopyrene derivatives and the like, and further substitutions such as aryls, heteroaryls, arylvinyls, aminos, cyanos, etc. to the compounds exemplified as the blue-blue-green and green-yellow dopant materials. A compound into which a group is introduced is also a suitable example. Further, a phosphorescent metal complex having iridium or platinum represented by tris (2-phenylpyridine) iridium (III) as a central metal is also a suitable example.

In addition, the dopant can be appropriately selected from compounds described in Chemical Industry, June 2004, page 13, and references cited therein.

Among the dopant materials described above, perylene derivatives, borane derivatives, amine-containing styryl derivatives, aromatic amine derivatives, coumarin derivatives, pyran derivatives, iridium complexes, or platinum complexes are particularly preferable.

Examples of perylene derivatives include 3,10-bis (2,6-dimethylphenyl) perylene, 3,10-bis (2,4,6-trimethylphenyl) perylene, 3,10-diphenylperylene, 3,4- Diphenylperylene, 2,5,8,11-tetra-t-butylperylene, 3,4,9,10-tetraphenylperylene, 3- (1'-pyrenyl) -8,11-di (t-butyl) perylene 3- (9′-anthryl) -8,11-di (t-butyl) perylene, 3,3′-bis (8,11-di (t-butyl) perylenyl), and the like.
JP-A-11-97178, JP-A-2000-133457, JP-A-2000-26324, JP-A-2001-267079, JP-A-2001-267078, JP-A-2001-267076, Perylene derivatives described in JP-A No. 2000-34234, JP-A No. 2001-267075, JP-A No. 2001-217077 and the like may be used.

Examples of the borane derivatives include 1,8-diphenyl-10- (dimesitylboryl) anthracene, 9-phenyl-10- (dimesitylboryl) anthracene, 4- (9′-anthryl) dimesitylborylnaphthalene, 4- (10 ′ -Phenyl-9'-anthryl) dimesitylborylnaphthalene, 9- (dimesitylboryl) anthracene, 9- (4'-biphenylyl) -10- (dimesitylboryl) anthracene, 9- (4 '-(N-carbazolyl) phenyl) And -10- (dimesitylboryl) anthracene.
Moreover, you may use the borane derivative described in the international publication 2000/40586 pamphlet.

Examples of amine-containing styryl derivatives include N, N, N ′, N′-tetra (4-biphenylyl) -4,4′-diaminostilbene, N, N, N ′, N′-tetra (1-naphthyl). -4,4'-diaminostilbene, N, N, N ', N'-tetra (2-naphthyl) -4,4'-diaminostilbene, N, N'-di (2-naphthyl) -N, N'-Diphenyl-4,4'-diaminostilbene, N, N'-di (9-phenanthryl) -N, N'-diphenyl-4,4'-diaminostilbene, 4,4'-bis [4 "-bis ( Diphenylamino) styryl] -biphenyl, 1,4-bis [4′-bis (diphenylamino) styryl] -benzene, 2,7-bis [4′-bis (diphenylamino) styryl] -9,9-dimethylfluorene 4,4'-bis (9-ethyl-3-carbazobi Nylene) -biphenyl, 4,4′-bis (9-phenyl-3-carbazovinylene) -biphenyl, and the like.
In addition, amine-containing styryl derivatives described in JP2003-347056A and JP2001-307884A may be used.

Examples of the aromatic amine derivative include N, N, N, N-tetraphenylanthracene-9,10-diamine, 9,10-bis (4-diphenylamino-phenyl) anthracene, and 9,10-bis (4- Di (1-naphthylamino) phenyl) anthracene, 9,10-bis (4-di (2-naphthylamino) phenyl) anthracene, 10-di-p-tolylamino-9- (4-di-p-tolylamino-1) -Naphthyl) anthracene, 10-diphenylamino-9- (4-diphenylamino-1-naphthyl) anthracene, 10-diphenylamino-9- (6-diphenylamino-2-naphthyl) anthracene, [4- (4-diphenyl) Amino-phenyl) naphthalen-1-yl] -diphenylamine, [4- (4-diphenylamino-phenyl) na Talen-1-yl] -diphenylamine, [6- (4-diphenylamino-phenyl) naphthalen-2-yl] -diphenylamine, 4,4′-bis [4-diphenylaminonaphthalen-1-yl] biphenyl, 4, 4'-bis [6-diphenylaminonaphthalen-2-yl] biphenyl, 4,4 "-bis [4-diphenylaminonaphthalen-1-yl] -p-terphenyl, 4,4" -bis [6-diphenyl Aminonaphthalen-2-yl] -p-terphenyl and the like.
Moreover, you may use the aromatic amine derivative described in Unexamined-Japanese-Patent No. 2006-156888.

Examples of coumarin derivatives include coumarin-6 and coumarin-334.
Moreover, you may use the coumarin derivative described in Unexamined-Japanese-Patent No. 2004-43646, Unexamined-Japanese-Patent No. 2001-76876, and Unexamined-Japanese-Patent No. 6-298758.

Examples of the pyran derivative include the following DCM and DCJTB.

Also, JP 2005-126399, JP 2005-097283, JP 2002-234892, JP 2001-220577, JP 2001-081090, and JP 2001-052869. Alternatively, pyran derivatives described in the above may be used.

Examples of the iridium complex include Ir (ppy) _{3 described} below.

Further, the iridium complexes described in JP-A-2006-089398, JP-A-2006-080419, JP-A-2005-298483, JP-A-2005-097263, JP-A-2004-111379, etc. It may be used.

Examples of the platinum complex include the following PtOEP.

Further, the platinum complexes described in JP-A-2006-190718, JP-A-2006-128634, JP-A-2006-093542, JP-A-2004-335122, JP-A-2004-331508, etc. It may be used.

<Electron injection layer and electron transport layer in organic electroluminescence device>
The electron injection layer 107 plays a role of efficiently injecting electrons moving from the cathode 108 into the light emitting layer 105 or the electron transport layer 106. The electron transport layer 106 plays a role of efficiently transporting electrons injected from the cathode 108 or electrons injected from the cathode 108 through the electron injection layer 107 to the light emitting layer 105. The electron transport layer 106 and the electron injection layer 107 are each formed by laminating and mixing one or more electron transport / injection materials or a mixture of the electron transport / injection material and the polymer binder.

The electron injection / transport layer is a layer that is responsible for injecting electrons from the cathode and further transporting the electrons. It is desirable that the electron injection efficiency is high and the injected electrons are transported efficiently. For this purpose, it is preferable to use a substance that has a high electron affinity, a high electron mobility, excellent stability, and is unlikely to generate trapping impurities during production and use. However, considering the transport balance between holes and electrons, if the role of effectively preventing the holes from the anode from flowing to the cathode side without recombination is mainly played, the electron transport capability is much higher. Even if it is not high, the effect of improving the luminous efficiency is equivalent to that of a material having a high electron transport capability. Therefore, the electron injection / transport layer in this embodiment may include a function of a layer that can efficiently block the movement of holes.

As the material (electron transport material) for forming the electron transport layer 106 or the electron injection layer 107, a compound represented by the above formula (1) can be used. Among these, in the present application, in particular, an embodiment in which a = 1 and b = 1, that is, a compound represented by the above formula (1-1) is preferably used.

The content of the compound represented by the above formula (1) in the electron transport layer 106 or the electron injection layer 107 differs depending on the type of the compound and may be determined according to the characteristics of the compound. The standard for the content of the compound represented by the formula (1) is preferably 1 to 100% by weight, more preferably 10 to 100% by weight, based on the whole electron transport layer material (or electron injection layer material). More preferably, it is 50 to 100% by weight, and particularly preferably 80 to 100% by weight. When the compound represented by the formula (1) is not used alone (100% by weight), other materials described in detail below may be mixed.

Other materials for forming the electron transport layer or electron injection layer include compounds conventionally used as electron transport compounds in photoconductive materials, and known materials used for electron injection layers and electron transport layers of organic electroluminescent devices. Any of these compounds can be selected and used.

As a material used for the electron transport layer or the electron injection layer, a compound composed of an aromatic ring or a heteroaromatic ring composed of one or more atoms selected from carbon, hydrogen, oxygen, sulfur, silicon, and phosphorus, pyrrole It is preferable to contain at least one selected from a derivative, a condensed ring derivative thereof, and a metal complex having an electron-accepting nitrogen. Specifically, condensed ring aromatic ring derivatives such as naphthalene and anthracene, styryl aromatic ring derivatives represented by 4,4′-bis (diphenylethenyl) biphenyl, perinone derivatives, coumarin derivatives, naphthalimide derivatives, anthraquinones And quinone derivatives such as diphenoquinone, phosphorus oxide derivatives, carbazole derivatives other than the compound represented by the above formula (1), and indole derivatives. Examples of metal complexes having electron-accepting nitrogen include hydroxyazole complexes such as hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes. These materials can be used alone or in combination with different materials. Among them, anthracene derivatives such as 9,10-bis (2-naphthyl) anthracene, styryl aromatic ring derivatives such as 4,4′-bis (diphenylethenyl) biphenyl, 4,4′-bis (N-carbazolyl) biphenyl A carbazole derivative such as 1,3,5-tris (N-carbazolyl) benzene is preferably used from the viewpoint of durability.

Further, as specific examples of other electron transfer compounds, pyridine derivatives other than the compound represented by the above formula (1), naphthalene derivatives, anthracene derivatives, phenanthroline derivatives, perinone derivatives, coumarin derivatives represented by the formula (1) , Naphthalimide derivatives, anthraquinone derivatives, diphenoquinone derivatives, diphenylquinone derivatives, perylene derivatives, oxadiazole derivatives (such as 1,3-bis [(4-tert-butylphenyl) 1,3,4-oxadiazolyl] phenylene), thiophene Derivatives, triazole derivatives (N-naphthyl-2,5-diphenyl-1,3,4-triazole, etc.), thiadiazole derivatives, metal complexes of oxine derivatives, quinolinol metal complexes, quinoxaline derivatives, polymers of quinoxaline derivatives, benzazole Compound, gallium complex, pyrazole derivative, perfluorinated phenylene derivative, triazine derivative, pyrazine derivative, benzoquinoline derivative (2,2′-bis (benzo [h] quinolin-2-yl) -9,9′-spirobifluorene Etc.), imidazopyridine derivatives, borane derivatives, benzimidazole derivatives (such as tris (N-phenylbenzoimidazol-2-yl) benzene), benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, oligopyridine derivatives such as terpyridine, bipyridine derivatives Terpyridine derivatives (such as 1,3-bis (4 ′-(2,2 ′: 6′2 ″ -terpyridinyl)) benzene), naphthyridine derivatives (bis (1-naphthyl) -4- (1,8-naphthyridine- 2-yl) phenylphosphine Side etc.), aldazine derivatives, carbazole derivatives other than the compounds represented by the above formula (1), indole derivatives, phosphorus oxide derivatives, such as bis-styryl derivatives.

In addition, metal complexes having electron-accepting nitrogen can also be used, such as hydroxyazole complexes such as quinolinol-based metal complexes and hydroxyphenyloxazole complexes, azomethine complexes, tropolone metal complexes, flavonol metal complexes, and benzoquinoline metal complexes. Is given.

The above-mentioned materials can be used alone, but they may be mixed with different materials.

Among the materials described above, quinolinol metal complexes, bipyridine derivatives, phenanthroline derivatives, borane derivatives or benzimidazole derivatives are preferable.

The quinolinol-based metal complex is a compound represented by the following general formula (E-1).

In the formula, R ¹ to R ⁶ are hydrogen or a substituent, M is Al, Ga, Be, or Zn, and n is an integer of 2 or 3.

Specific examples of quinolinol-based metal complexes include tris (8-quinolinolato) aluminum, tris (4-methyl-8-quinolinolato) aluminum, tris (5-methyl-8-quinolinolato) aluminum, tris (3,4-dimethyl-). 8-quinolinolato) aluminum, tris (4,5-dimethyl-8-quinolinolato) aluminum, tris (4,6-dimethyl-8-quinolinolato) aluminum, bis (2-methyl-8-quinolinolato) (phenolate) aluminum, bis (2-methyl-8-quinolinolato) (2-methylphenolato) aluminum, bis (2-methyl-8-quinolinolato) (3-methylphenolato) aluminum, bis (2-methyl-8-quinolinolato) (4- Methyl phenolate) Aluminum Bis (2-methyl-8-quinolinolato) (2-phenylphenolato) aluminum, bis (2-methyl-8-quinolinolato) (3-phenylphenolato) aluminum, bis (2-methyl-8-quinolinolato) (4-Phenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,3-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,6-dimethylphenolate) aluminum Bis (2-methyl-8-quinolinolato) (3,4-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (3,5-dimethylphenolato) aluminum, bis (2-methyl-8) -Quinolinolate) (3,5-Di-t-butylphenolate) Aluminum Bis (2-methyl-8-quinolinolato) (2,6-diphenylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,4,6-triphenylphenolato) aluminum, bis (2 -Methyl-8-quinolinolato) (2,4,6-trimethylphenolate) aluminum, bis (2-methyl-8-quinolinolato) (2,4,5,6-tetramethylphenolato) aluminum, bis (2- Methyl-8-quinolinolato) (1-naphtholato) aluminum, bis (2-methyl-8-quinolinolato) (2-naphtholato) aluminum, bis (2,4-dimethyl-8-quinolinolato) (2-phenylphenolato) aluminum Bis (2,4-dimethyl-8-quinolinolato) (3-phenylphenola) ) Aluminum, bis (2,4-dimethyl-8-quinolinolato) (4-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolato) (3,5-dimethylphenolate) aluminum, bis (2,4-Dimethyl-8-quinolinolato) (3,5-di-t-butylphenolate) aluminum, bis (2-methyl-8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-8- Quinolinolato) aluminum, bis (2,4-dimethyl-8-quinolinolato) aluminum-μ-oxo-bis (2,4-dimethyl-8-quinolinolato) aluminum, bis (2-methyl-4-ethyl-8-quinolinolato) Aluminum-μ-oxo-bis (2-methyl-4-ethyl-8-quinolinolato) aluminum Bis (2-methyl-4-methoxy-8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-4-methoxy-8-quinolinolato) aluminum, bis (2-methyl-5-cyano-8- Quinolinolato) aluminum-μ-oxo-bis (2-methyl-5-cyano-8-quinolinolato) aluminum, bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum-μ-oxo-bis (2- Methyl-5-trifluoromethyl-8-quinolinolato) aluminum, bis (10-hydroxybenzo [h] quinoline) beryllium and the like.

The bipyridine derivative is a compound represented by the following general formula (E-2).

In the formula, G represents a simple bond or an n-valent linking group, and n is an integer of 2 to 8. Further, carbon not used for bonding of pyridine-pyridine or pyridine-G may be substituted.

Examples of G in the general formula (E-2) include the following structural formulas. In the following structural formulas, each R is independently hydrogen, methyl, ethyl, isopropyl, cyclohexyl, phenyl, 1-naphthyl, 2-naphthyl, biphenylyl or terphenylyl.

Specific examples of the pyridine derivative include 2,5-bis (2,2′-bipyridin-6-yl) -1,1-dimethyl-3,4-diphenylsilole, 2,5-bis (2,2′- Bipyridin-6-yl) -1,1-dimethyl-3,4-dimesitylsilole, 2,5-bis (2,2′-bipyridin-5-yl) -1,1-dimethyl-3,4 Diphenylsilole, 2,5-bis (2,2′-bipyridin-5-yl) -1,1-dimethyl-3,4-dimesitylsilole 9,10-di (2,2′-bipyridine-6- Yl) anthracene, 9,10-di (2,2′-bipyridin-5-yl) anthracene, 9,10-di (2,3′-bipyridin-6-yl) anthracene, 9,10-di (2, 3′-bipyridin-5-yl) anthracene, 9,10-di (2, '-Bipyridin-6-yl) -2-phenylanthracene, 9,10-di (2,3'-bipyridin-5-yl) -2-phenylanthracene, 9,10-di (2,2'-bipyridine) 6-yl) -2-phenylanthracene, 9,10-di (2,2′-bipyridin-5-yl) -2-phenylanthracene, 9,10-di (2,4′-bipyridin-6-yl) -2-Phenylanthracene, 9,10-di (2,4′-bipyridin-5-yl) -2-phenylanthracene, 9,10-di (3,4′-bipyridin-6-yl) -2-phenyl Anthracene, 9,10-di (3,4'-bipyridin-5-yl) -2-phenylanthracene, 3,4-diphenyl-2,5-di (2,2'-bipyridin-6-yl) thiophene, 3,4-dipheni -2,5-di (2,3′-bipyridin-5-yl) thiophene, 6′6 ″ -di (2-pyridyl) 2,2 ′: 4 ′, 4 ″: 2 ″, 2 ″ ′-qua Examples include terpyridine.

The phenanthroline derivative is a compound represented by the following general formula (E-3-1) or (E-3-2).

In the formula, R ¹ to R ⁸ are hydrogen or a substituent, adjacent groups may be bonded to each other to form a condensed ring, G represents a simple bond or an n-valent linking group, and n represents 2 It is an integer of ~ 8. Examples of G in the general formula (E-3-2) include the same ones as described in the bipyridine derivative column.

Specific examples of phenanthroline derivatives include 4,7-diphenyl-1,10-phenanthroline, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, 9,10-di (1,10-phenanthroline- 2-yl) anthracene, 2,6-di (1,10-phenanthroline-5-yl) pyridine, 1,3,5-tri (1,10-phenanthroline-5-yl) benzene, 9,9′-difluor -Bis (1,10-phenanthroline-5-yl), bathocuproin, 1,3-bis (2-phenyl-1,10-phenanthroline-9-yl) benzene and the like.

In particular, the case where a phenanthroline derivative is used for the electron transport layer and the electron injection layer will be described. In order to obtain stable light emission over a long period of time, a material excellent in thermal stability and thin film formation is desired, and among phenanthroline derivatives, the substituent itself has a three-dimensional structure, or a phenanthroline skeleton or Those having a three-dimensional structure by steric repulsion with an adjacent substituent or those having a plurality of phenanthroline skeletons linked to each other are preferred. Furthermore, when linking a plurality of phenanthroline skeletons, a compound containing a conjugated bond, a substituted or unsubstituted aromatic hydrocarbon, or a substituted or unsubstituted aromatic heterocycle in the linking unit is more preferable.

The borane derivative is a compound represented by the following general formula (E-4), and is disclosed in detail in JP-A-2007-27587.

Wherein R ¹¹ and R ¹² are each independently at least one of hydrogen, alkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano, R ¹³ to R ¹⁶ are each independently an optionally substituted alkyl or an optionally substituted aryl, X is an optionally substituted arylene, and Y is a substituted Aryl having 16 or less carbon atoms, substituted boryl, or optionally substituted carbazole, and each n is independently an integer of 0 to 3.

Among the compounds represented by the general formula (E-4), compounds represented by the following general formula (E-4-1), and further the following general formulas (E-4-1-1) to (E-4) The compound represented by -1-4) is preferred. Specific examples include 9- [4- (4-Dimesitylborylnaphthalen-1-yl) phenyl] carbazole, 9- [4- (4-Dimesitylborylnaphthalen-1-yl) naphthalen-1-yl. Carbazole and the like.

Wherein R ¹¹ and R ¹² are each independently at least one of hydrogen, alkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano, R ¹³ to R ¹⁶ are each independently an optionally substituted alkyl or an optionally substituted aryl, and R ²¹ and R ²² are each independently hydrogen, alkyl, or substituted. At least one of optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocyclic ring, or cyano, X ¹ is an optionally substituted arylene having 20 or less carbon atoms, and n is each Each independently represents an integer of 0 to 3, and each m independently represents an integer of 0 to 4;

In each formula, R ³¹ to R ³⁴ are each independently methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are each independently hydrogen, methyl, isopropyl or phenyl. It is.

Among the compounds represented by the above general formula (E-4), a compound represented by the following general formula (E-4-2), and a compound represented by the following general formula (E-4-2-1) Is preferred.

In which R ¹¹ and R ¹² are each independently at least one of hydrogen, alkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano, R ¹³ to R ¹⁶ are each independently an optionally substituted alkyl or an optionally substituted aryl; X ¹ is an optionally substituted arylene having 20 or less carbon atoms; N is an integer of 0 to 3 independently.

In the formula, R ³¹ to R ³⁴ are each independently any of methyl, isopropyl or phenyl, and R ³⁵ and R ³⁶ are each independently any of hydrogen, methyl, isopropyl or phenyl It is.

Among the compounds represented by the above general formula (E-4), compounds represented by the following general formula (E-4-3-3), and further represented by the following general formula (E-4-3-1) or (E-4) The compound represented by -3-2) is preferable.

Wherein R ¹¹ and R ¹² are each independently at least one of hydrogen, alkyl, optionally substituted aryl, substituted silyl, optionally substituted nitrogen-containing heterocycle, or cyano, R ¹³ to R ¹⁶ are each independently an optionally substituted alkyl or an optionally substituted aryl; X ¹ is an optionally substituted arylene having 10 or less carbon atoms; Y ¹ is an optionally substituted aryl having 14 or less carbon atoms, and n is each independently an integer of 0 to 3.

The benzimidazole derivative is a compound represented by the following general formula (E-5).

In the formula, Ar ¹ to Ar ³ are each independently hydrogen or aryl having 6 to 30 carbon atoms which may be substituted. In particular, a benzimidazole derivative which is anthryl optionally substituted with Ar ¹ is preferable.

Specific examples of aryl having 6 to 30 carbon atoms include phenyl, 1-naphthyl, 2-naphthyl, acenaphthylene-1-yl, acenaphthylene-3-yl, acenaphthylene-4-yl, acenaphthylene-5-yl, and fluorene-1- Yl, fluoren-2-yl, fluoren-3-yl, fluoren-4-yl, fluoren-9-yl, phenalen-1-yl, phenalen-2-yl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl, 9-phenanthryl, 1-anthryl, 2-anthryl, 9-anthryl, fluoranthen-1-yl, fluoranthen-2-yl, fluoranthen-3-yl, fluoranthen-7-yl, fluoranthen-8-yl, Triphenylene-1-yl, triphenylene-2-yl, pi N-1-yl, pyren-2-yl, pyren-4-yl, chrysen-1-yl, chrysen-2-yl, chrysen-3-yl, chrysen-4-yl, chrysen-5-yl, chrysene- 6-yl, naphthacene-1-yl, naphthacene-2-yl, naphthacene-5-yl, perylene-1-yl, perylene-2-yl, perylene-3-yl, pentacene-1-yl, pentacene-2- Yl, pentacene-5-yl and pentacene-6-yl.

Specific examples of the benzimidazole derivative include 1-phenyl-2- (4- (10-phenylanthracen-9-yl) phenyl) -1H-benzo [d] imidazole, 2- (4- (10- (naphthalene-2) -Yl) anthracen-9-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole, 2- (3- (10- (naphthalen-2-yl) anthracen-9-yl) phenyl) -1- Phenyl-1H-benzo [d] imidazole, 5- (10- (naphthalen-2-yl) anthracen-9-yl) -1,2-diphenyl-1H-benzo [d] imidazole, 1- (4- (10 -(Naphthalen-2-yl) anthracen-9-yl) phenyl) -2-phenyl-1H-benzo [d] imidazole, 2- (4- (9,10-di (naphthalene) -2-yl) anthracen-2-yl) phenyl) -1-phenyl-1H-benzo [d] imidazole, 1- (4- (9,10-di (naphthalen-2-yl) anthracen-2-yl) Phenyl) -2-phenyl-1H-benzo [d] imidazole, 5- (9,10-di (naphthalen-2-yl) anthracen-2-yl) -1,2-diphenyl-1H-benzo [d] imidazole It is.

The electron transport layer or the electron injection layer may further contain a substance capable of reducing the material forming the electron transport layer or the electron injection layer. As this reducing substance, various substances can be used as long as they have a certain reducing ability. For example, alkali metal, alkaline earth metal, rare earth metal, alkali metal oxide, alkali metal halide, alkali Group consisting of earth metal oxides, alkaline earth metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes, and rare earth metal organic complexes At least one selected from can be preferably used.
Preferred reducing substances include alkali metals such as Na (work function 2.36 eV), K (2.28 eV), Rb (2.16 eV) or Cs (1.95 eV), and Ca (2. 9eV), Sr (2.0 to 2.5 eV) or Ba (2.52 eV), and alkaline earth metals such as those having a work function of 2.9 eV or less are particularly preferable. Among these, a more preferable reducing substance is an alkali metal of K, Rb or Cs, more preferably Rb or Cs, and most preferably Cs. These alkali metals have particularly high reducing ability, and by adding a relatively small amount to the material forming the electron transport layer or the electron injection layer, the luminance of the organic EL element can be improved and the lifetime can be extended. Further, as a reducing substance having a work function of 2.9 eV or less, a combination of two or more alkali metals is also preferable. Particularly, a combination containing Cs, such as Cs and Na, Cs and K, Cs and Rb, or A combination of Cs, Na and K is preferred. By containing Cs, the reducing ability can be efficiently exhibited, and by adding to the material for forming the electron transport layer or the electron injection layer, the luminance of the organic EL element can be improved and the lifetime can be extended.

<Cathode in organic electroluminescence device>
The cathode 108 serves to inject electrons into the light emitting layer 105 through the electron injection layer 107 and the electron transport layer 106.

The material for forming the cathode 108 is not particularly limited as long as it is a substance that can efficiently inject electrons into the organic layer, but the same material as that for forming the anode 102 can be used. Among them, metals such as tin, magnesium, indium, calcium, aluminum, silver, copper, nickel, chromium, gold, platinum, iron, zinc, lithium, sodium, potassium, cesium, and magnesium or their alloys (magnesium-silver Alloys, magnesium-indium alloys, aluminum-lithium alloys such as lithium fluoride / aluminum) and the like are preferred. In order to increase the electron injection efficiency and improve the device characteristics, lithium, sodium, potassium, cesium, calcium, magnesium, or alloys containing these low work function metals are effective. However, these low work function metals are often often unstable in the atmosphere. In order to improve this point, for example, a method is known in which an organic layer is doped with a small amount of lithium, cesium or magnesium and a highly stable electrode is used. As other dopants, inorganic salts such as lithium fluoride, cesium fluoride, lithium oxide, and cesium oxide can also be used. However, it is not limited to these.

Further, for electrode protection, metals such as platinum, gold, silver, copper, iron, tin, aluminum, and indium, or alloys using these metals, and inorganic substances such as silica, titania, and silicon nitride, polyvinyl alcohol, Preferred examples include laminating vinyl chloride, hydrocarbon polymer compounds and the like. The method for producing these electrodes is not particularly limited as long as conduction can be achieved, such as resistance heating, electron beam, sputtering, ion plating, and coating.

<Binder that may be used in each layer>
The materials used for the above hole injection layer, hole transport layer, light emitting layer, electron transport layer, and electron injection layer can form each layer alone, but as a polymer binder, polyvinyl chloride, polycarbonate , Polystyrene, poly (N-vinylcarbazole), polymethyl methacrylate, polybutyl methacrylate, polyester, polysulfone, polyphenylene oxide, polybutadiene, hydrocarbon resin, ketone resin, phenoxy resin, polyamide, ethyl cellulose, vinyl acetate resin, ABS resin, polyurethane Can be used by being dispersed in solvent-soluble resins such as resins, and curable resins such as phenol resins, xylene resins, petroleum resins, urea resins, melamine resins, unsaturated polyester resins, alkyd resins, epoxy resins, and silicone resins. Is

<Method for producing organic electroluminescent element>
Each layer constituting the organic electroluminescent element is formed by a method such as vapor deposition, resistance heating vapor deposition, electron beam vapor deposition, sputtering, molecular lamination method, printing method, spin coating method, casting method, or coating method. The film can be formed by forming a thin film. The film thickness of each layer thus formed is not particularly limited and can be appropriately set according to the properties of the material, but is usually in the range of 2 nm to 5000 nm. The film thickness can usually be measured with a crystal oscillation type film thickness measuring device or the like. When a thin film is formed using a vapor deposition method, the vapor deposition conditions vary depending on the type of material, the target crystal structure and association structure of the film, and the like. Deposition conditions generally include boat heating temperature +50 to + 400 ° C., vacuum degree 10 ⁻⁶ to 10 ⁻³ Pa, deposition rate 0.01 to 50 nm / second, substrate temperature −150 to + 300 ° C., film thickness 2 nm to 5 μm. It is preferable to set appropriately within the range.

Next, as an example of a method for producing an organic electroluminescent device, an organic electric field composed of an anode / hole injection layer / hole transport layer / a light emitting layer composed of a host material and a dopant material / electron transport layer / electron injection layer / cathode. A method for manufacturing a light-emitting element will be described. A thin film of an anode material is formed on a suitable substrate by vapor deposition or the like to produce an anode, and then a thin film of a hole injection layer and a hole transport layer is formed on the anode. A host material and a dopant material are co-evaporated to form a thin film to form a light emitting layer. An electron transport layer and an electron injection layer are formed on the light emitting layer, and a thin film made of a cathode material is formed by vapor deposition. By forming it as a cathode, a desired organic electroluminescent element can be obtained. In the preparation of the organic electroluminescence device described above, the order of preparation may be reversed, and the cathode, electron injection layer, electron transport layer, light emitting layer, hole transport layer, hole injection layer, and anode may be fabricated in this order. Is possible.

When a DC voltage is applied to the organic electroluminescent device thus obtained, the anode may be applied with a positive polarity and the cathode with a negative polarity. When a voltage of about 2 to 40 V is applied, the organic electroluminescent device is transparent or translucent. Luminescence can be observed from the electrode side (anode or cathode, and both). The organic electroluminescence device emits light when a pulse current or an alternating current is applied. The alternating current waveform to be applied may be arbitrary.

<Application examples of organic electroluminescent devices>
The present invention can also be applied to a display device provided with an organic electroluminescent element or a lighting device provided with an organic electroluminescent element.
A display device or an illuminating device including an organic electroluminescent element can be manufactured by a known method such as connecting the organic electroluminescent element according to the present embodiment and a known driving device, such as direct current driving, pulse driving, or alternating current. It can be driven by appropriately using a known driving method such as driving.

Examples of the display device include a panel display such as a color flat panel display, and a flexible display such as a flexible color organic electroluminescence (EL) display (for example, JP-A-10-335066 and JP-A-2003-321546). Gazette, JP-A-2004-281086, etc.). Examples of the display method of the display include a matrix and / or segment method. Note that the matrix display and the segment display may coexist in the same panel.

A matrix is a pixel in which pixels for display are arranged two-dimensionally, such as a grid or mosaic, and displays characters and images as a set of pixels. The shape and size of the pixel are determined by the application. For example, a square pixel with a side of 300 μm or less is usually used for displaying images and characters on a personal computer, monitor, TV, and a pixel with a side of mm order for a large display such as a display panel. become. In monochrome display, pixels of the same color may be arranged. However, in color display, red, green, and blue pixels are displayed side by side. In this case, there are typically a delta type and a stripe type. The matrix driving method may be either a line sequential driving method or an active matrix. The line-sequential driving has an advantage that the structure is simple. However, the active matrix may be superior in consideration of the operation characteristics, so that it is necessary to properly use it depending on the application.

In the segment method (type), a pattern is formed so as to display predetermined information, and a predetermined region is caused to emit light. For example, the time and temperature display in a digital clock or a thermometer, the operation status display of an audio device or an electromagnetic cooker, the panel display of an automobile, and the like can be given.

Examples of the illuminating device include an illuminating device such as indoor lighting, a backlight of a liquid crystal display device, and the like (for example, JP 2003-257621 A, JP 2003-277741 A, JP 2004-119211 A). Etc.) The backlight is mainly used for the purpose of improving the visibility of a display device that does not emit light, and is used for a liquid crystal display device, a clock, an audio device, an automobile panel, a display board, a sign, and the like. In particular, as a backlight for liquid crystal display devices, especially personal computers for which thinning is an issue, considering that conventional methods are made of fluorescent lamps and light guide plates, it is difficult to reduce the thickness. The backlight using the light emitting element according to the embodiment is thin and lightweight.

Synthesis of 2,7-dimethoxy-9- (naphthalen-1-yl) -9H-carbazole 2,7-dimethoxy-9H-carbazole (10 g) synthesized according to a method described in known literature, 1-fluoronaphthalene ( 9.7 g), a flask containing cesium carbonate (17.2 g) and dimethyl sulfoxide (150 ml) was stirred at 150 ° C. for 11 hours under a nitrogen atmosphere. Thereafter, the reaction solution was cooled to room temperature, the precipitate was separated by suction filtration, water and toluene were added, and a water washing operation was performed. Subsequently, the residue was purified by silica gel chromatography (toluene / ethyl acetate = 5/1 (volume ratio)) to obtain 2,7-dimethoxy-9- (naphthalen-1-yl) -9H-carbazole (12.4 g).

Synthesis of 9- (naphthalen-1-yl) -9H-carbazole-2,7-diol 2,7-dimethoxy-9- (naphthalen-1-yl) -9H-carbazole (12 0.0 g) was dissolved in dichloromethane (100 ml) under a nitrogen atmosphere and cooled with brine. Boron tribromide in 1M dichloromethane (75 ml) was added dropwise thereto, and after completion of the dropwise addition, the mixture was stirred at room temperature for 16 hours. The reaction was stopped by adding water, and the solution neutralized with aqueous sodium hydrogen carbonate was separated using a separatory funnel. The dichloromethane layer was concentrated and purified by silica gel column chromatography (toluene / ethyl acetate = 10/1 (volume ratio)), and 9- (naphthalen-1-yl) -9H-carbazole-2,7-diol (11. 1 g) was obtained.

Synthesis of 9- (naphthalen-1-yl) -9H-carbazole-2,7-diyl bis (trifluoromethanesulfonic acid) 9- (naphthalen-1-yl) -9H-carbazole- obtained as described above 2,7-diol (11.0 g) was dissolved in pyridine (100 ml) under a nitrogen atmosphere and cooled with ice water. Trifluoromethanesulfonic anhydride (25 g) was added dropwise thereto, and the mixture was stirred at room temperature for 15 hours after completion of the addition. Water was added to stop the reaction, and the reaction solution was transferred to a separatory funnel and extracted with ethyl acetate. The solid obtained by concentrating with an evaporator was washed with methanol, water and methanol in this order, and then recrystallized from a mixed solvent of THF / ethanol to give 9- (naphthalen-1-yl) -9H-carbazole-2,7 -Diyl bis (trifluoromethanesulfonic acid) (12.7 g) was obtained.

Synthesis of 9- (naphthalen-1-yl) -2,7-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9H-carbazole Cyclopentyl methyl ether (100 ml ) 9- (naphthalen-1-yl) -9H-carbazole-2,7-diyl bis (trifluoromethanesulfonic acid) (9.5 g) and bis (pinacolato) diboron (9. 0 g) was added with stirring bis (dibenzylideneacetone) palladium (0) (1.4 g), tricyclohexylphosphine (1.6 g) and potassium acetate (4.7 g) at room temperature under a nitrogen atmosphere. added. Then, after stirring at reflux temperature for 4 hours, the reaction solution was cooled to room temperature, toluene was added, and the precipitate was separated by suction filtration. The filtrate was concentrated with an evaporator and purified by silica gel column chromatography (toluene). Subsequently, recrystallization from a dichloromethane / ethanol mixed solvent 9- (naphthalen-1-yl) -2,7-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)- 9H-carbazole (3.6 g) was obtained.

Synthesis of compound represented by formula (1-1-856); 9- (naphthalen-1-yl) -2,7-bis (3- (pyridin-4-yl) phenyl) -9H-carbazole 9- (Naphthalen-1-yl) -2,7-bis (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9H-carbazole (3 0.5 g), 4- (3-bromophenyl) pyridine (3.3 g), sodium carbonate (2.7 g), and Pd (PPh ₃ ) ₄ (0.5 g) under an argon atmosphere with toluene ( 30 ml), ethanol (10 ml) and water (10 ml) were added and stirred at reflux temperature for 13 hours. The reaction solution was cooled to room temperature, water was added, and washing operation was performed. The organic substance from which salts have been removed by washing with water is purified by activated alumina column chromatography (toluene / ethyl acetate = 1/4 (volume ratio)), and finally the compound represented by the formula (1-1-856) 9- (Naphthalen-1-yl) -2,7-bis (3- (pyridin-4-yl) phenyl) -9H-carbazole (1.1 g) was obtained.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (500 MHz, CDCl ₃ ): δ = 8.65 (dd, 4H), 8.3 (d, 2H), 8.08 (dd, 1H), 8.04 (d, 1H), 7 .77 (m, 2H), 7.68-7.75 (m, 2H), 7.52-7.62 (m, 7H), 7.45-7.49 (m, 6H), 7.35 -7.41 (m, 2H), 7.21 (m, 2H).

Synthesis of 9- (Naphthalen-1-yl) -2,7-bis (3- (pyridin-2-yl) phenyl) -9H-carbazole 9- (Naphthalen-1-yl) -2,7-bis (4 , 4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9H-carbazole (3.0 g), 2- (3-bromophenyl) pyridine (3.2 g), potassium carbonate ( 3.0 g) and PdCl ₂ {P (t-Bu) _2- (p-NMe ₂ -Ph)} ₂ (Johnson Massey, Pd-132) (0.05 g) in an argon atmosphere. Below, toluene (25 ml) and water (2.5 ml) were added, and the mixture was stirred at reflux temperature for 6 hours. After cooling the reaction solution to room temperature, toluene and water were added for liquid separation, and toluene was distilled off under reduced pressure. The obtained concentrate was purified by amino group-modified silica gel (NH DM1020: manufactured by Fuji Silysia) column chromatography (heptane / ethyl acetate = 3/1 (volume ratio)). Subsequently, the product is purified by activated alumina column chromatography (toluene / ethyl acetate = 50/1 (volume ratio)), and finally 9- (naphthalene-1) which is a compound represented by the formula (1-1-854) -Il) -2,7-bis (3- (pyridin-2-yl) phenyl) -9H-carbazole (0.9 g) was obtained.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.67 (m, 2H), 8.29 (d, 2H), 8.16 (m, 2H), 8.05 (d, 1H), 8.01 (D, 1H), 7.88 (d, 2H), 7.66-7.74 (m, 6H), 7.65 (d, 2H), 7.56 (d, 2H), 7.53 ( t, 1H), 7.45 (t, 2H), 7.40 (d, 1H), 7.15 (t, 1H), 7.25 (m, 2H), 7.20 (m, 2H).

Synthesis of 9- (Naphthalen-1-yl) -2,7-bis (3- (pyridin-3-yl) phenyl) -9H-carbazole 9- (Naphthalen-1-yl) -2,7-bis (4 , 4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9H-carbazole (3.0 g), 3- (3-bromophenyl) pyridine (3.2 g), potassium carbonate ( 3.0 g) and PdCl ₂ {P (t-Bu) _2- (p-NMe ₂ -Ph)} ₂ (Johnson Massey, Pd-132) (0.04 g) in an argon atmosphere. Then, toluene (25 ml) and water (2.5 ml) were added, and the mixture was stirred at reflux temperature for 4 and a half hours. After cooling the reaction solution to room temperature, toluene and water were added for liquid separation, and toluene was distilled off under reduced pressure. The obtained concentrate was purified by activated alumina column chromatography (toluene / ethyl acetate = 5/1 (volume ratio)). Subsequently, it is purified by column chromatography (heptane / ethyl acetate = 3/1 (volume ratio)) with amino group-modified silica gel (NH DM1020: manufactured by Fuji Silysia), and finally represented by the formula (1-1-855) The compound 9- (naphthalen-1-yl) -2,7-bis (3- (pyridin-3-yl) phenyl) -9H-carbazole (0.7 g) was obtained.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.83 (m, 2H), 8.58 (m, 2H), 8.30 (d, 2H), 8.07 (d, 1H), 8.02 (D, 1H), 7.85 (d, 2H), 7.67-7.78 (m, 4H), 7.61 (d, 2H), 7.56 (m, 3H), 7.49 ( m, 4H), 7.30-7.40 (m, 4H), 7.21 (s, 2H).

Synthesis of 9- (Naphthalen-1-yl) -2,7-bis (4- (pyridin-2-yl) phenyl) -9H-carbazole 9- (Naphthalen-1-yl) -2,7-bis (4 , 4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9H-carbazole (3.0 g), 2- (4-bromophenyl) pyridine (2.8 g), sodium carbonate ( 2.4 g) and Pd (PPh ₃ ) ₄ (0.2 g) were charged with toluene (17 ml), ethanol (6 ml) and water (6 ml) under an argon atmosphere and stirred at reflux temperature for 12 hours and a half. did. After cooling the reaction solution to room temperature, water was added and a solid was obtained by suction filtration. Subsequently, the obtained solid was purified by activated alumina column column chromatography (developing solution: chlorobenzene / ethyl acetate mixed solvent). At this time, referring to the method described in “Chemical Doujinshi Publishing Co., Ltd., page 94”, gradually increase the ratio of ethyl acetate in the developing solution. The target product was eluted by increasing the amount to 1. Subsequently, recrystallization from orthodichlorobenzene and finally 9- (naphthalen-1-yl) -2,7-bis (4- (pyridine-), which is a compound represented by the formula (1-1-851) 2-yl) phenyl) -9H-carbazole (1.0 g) was obtained.

An attempt was made to confirm the structure of the compound obtained by NMR measurement, but because of low solubility, the resolution was poor and could not be confirmed well. However, liquid chromatography mass spectrometry (LCMS) confirmed the molecular weight of the target compound represented by the formula (1-1-851).

Synthesis of 9- (Naphthalen-1-yl) -2,7-bis (4- (pyridin-3-yl) phenyl) -9H-carbazole 9- (Naphthalen-1-yl) -2,7-bis (4 , 4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9H-carbazole (3.0 g), 3- (4-bromophenyl) pyridine (3.2 g), potassium carbonate ( 3.0 g) and PdCl ₂ {P (t-Bu) _2- (p-NMe ₂ -Ph)} ₂ (Johnson Massey, Pd-132) (0.04 g) in an argon atmosphere. Then, toluene (25 ml) and water (2.5 ml) were added, and the mixture was stirred at reflux temperature for 5 and a half hours. After cooling the reaction solution to room temperature, water was added and a solid was obtained by suction filtration. The obtained solid was washed with water and then with methanol. Further, recrystallization from N, N-dimethylformamide and finally 9- (naphthalen-1-yl) -2,7-bis (4-), which is a compound represented by the formula (1-1-852) (Pyridin-3-yl) phenyl) -9H-carbazole (0.7 g) was obtained.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.85 (m, 2H), 8.57 (dd, 2H), 8.30 (d, 2H), 8.10 (m, 1H), 8.05 (D, 1H), 7.86 (m, 2H), 7.72 (m, 2H), 7.66 (m, 4H), 7.62 (dd, 2H), 7.55 to 7.60 ( m, 5H), 7.32-7.41 (m, 4H), 7.23 (m, 2H).

Synthesis of 9- (Naphthalen-1-yl) -2,7-bis (4- (pyridin-4-yl) phenyl) -9H-carbazole 9- (Naphthalen-1-yl) -2,7-bis (4 , 4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) -9H-carbazole (3.0 g), 3- (4-bromophenyl) pyridine (3.2 g), potassium carbonate ( 3.0 g) and PdCl ₂ {P (t-Bu) _2- (p-NMe ₂ -Ph)} ₂ (Johnson Massey, Pd-132) (0.04 g) in an argon atmosphere. Then, toluene (25 ml) and water (2.5 ml) were added, and the mixture was stirred at reflux temperature for 6 and a half hours. After cooling the reaction solution to room temperature, water was added and a solid was obtained by suction filtration. The obtained solid was washed with water, then with methanol and further with ethyl acetate, and further purified by activated alumina column column chromatography (developing solution: chlorobenzene / ethyl acetate mixed solvent). At this time, the target product was eluted by gradually increasing the ratio of ethyl acetate in the developing solution. The solvent was distilled off under reduced pressure, and then recrystallized from chlorobenzene and then N, N-dimethylformamide, and finally 9- (naphthalen-1-yl, which is a compound represented by the formula (1-1-853) ) -2,7-bis (4- (pyridin-4-yl) phenyl) -9H-carbazole (0.5 g) was obtained.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.64 (m, 4H), 8.31 (d, 2H), 8.12 (t, 1H), 8.06 (d, 1H), 7.73 (M, 2H), 7.60-7.70 (m, 10H), 7.57 (m, 1H), 7.49 (m, 4H), 7.39 (m, 2H), 7.23 ( m, 2H).

Synthesis of 9-([1,1′-biphenyl] -3-yl) -2,7-dibromo-9H-carbazole 2,7-bromo-9H-carbazole (26.9 g), 3-fluoro-1,1 A flask containing '-biphenyl (21.4 g), cesium carbonate (40.5 g) and dimethyl sulfoxide (400 ml) was stirred at 170 ° C. for 22 and a half hours under a nitrogen atmosphere. Then, the reaction liquid was cooled to room temperature, and water and ethyl acetate were added and liquid-separated. Ethyl acetate was distilled off under reduced pressure, and the resulting solid was dissolved in heated chloroform and filtered while hot. The obtained filtrate was adsorbed on silica gel, dried, and charged in silica gel chromatography (developing solution: heptane / toluene mixed solvent) prepared separately. The target product was eluted by gradually increasing the ratio of toluene in the developing solution. Further, recrystallization from heptane gave 9-([1,1′-biphenyl] -3-yl) -2,7-dibromo-9H-carbazole (4.2 g).

Synthesis of 9-([1,1′-biphenyl] -3-yl) -2,7-bis (4- (pyridin-2-yl) phenyl) -9H-carbazole First, using a palladium catalyst, By coupling reaction of (4-bromophenyl) pyridine and bispinacolatodiboron, 2- (4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) Phenyl) pyridine was synthesized. Next, 9-([1,1′-biphenyl] -3-yl) -2,7-dibromo-9H-carbazole (1.5 g), 2- (4- (4,4,5,5-tetra Methyl-1,3,2-dioxaborolan-2-yl) phenyl) pyridine (1.8 g), potassium carbonate (1.7 g) and PdCl ₂ {P (t-Bu) _2- (p-NMe ₂ -Ph) } Toluene (15 ml) and water (3 ml) were placed in a flask containing ₂ (manufactured by Johnson Matthey, Pd-132) (0.06 g) under an argon atmosphere, and stirred at reflux temperature for 8 hours. The reaction solution was cooled to room temperature, and water and chloroform were added for liquid separation. Chloroform was distilled off under reduced pressure, and the resulting solid was purified by amino group-modified silica gel (NH DM1020: manufactured by Fuji Silysia) column chromatography (heptane / toluene = 1/2 (volume ratio)). The solvent was distilled off under reduced pressure, followed by washing with ethyl acetate, and finally 9-([1,1′-biphenyl] -3-yl), which is a compound represented by the formula (1-1-1198). -2,7-bis (4- (pyridin-2-yl) phenyl) -9H-carbazole (0.3 g) was obtained.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.70 (m, 2H), 8.23 (d, 2H), 8.07 (d, 4H), 7.87 (m, 1H), 7.60 -7.80 (m, 17H), 7.46 (t, 2H), 7.37 (t, 1H), 7.22 (m, 2H).

Synthesis of 9-([1,1′-biphenyl] -3-yl) -2,7-bis (3- (pyridin-3-yl) phenyl) -9H-carbazole First, using a palladium catalyst, By coupling reaction of (3-bromophenyl) pyridine and bispinacolatodiboron, 3- (3- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) Phenyl) pyridine was synthesized. Next, 9-([1,1′-biphenyl] -3-yl) -2,7-dibromo-9H-carbazole (1.5 g), 3- (3- (4,4,5,5-tetra Methyl-1,3,2-dioxaborolan-2-yl) phenyl) pyridine (1.8 g), potassium carbonate (1.7 g) and PdCl ₂ {P (t-Bu) _2- (p-NMe ₂ -Ph) } Toluene (15 ml) and water (3 ml) were placed in a flask containing ₂ (manufactured by Johnson Matthey, Pd-132) (0.06 g) under an argon atmosphere, and stirred at reflux temperature for 11 hours. The reaction solution was cooled to room temperature, and water and toluene were added for liquid separation. Toluene was distilled off under reduced pressure, and the resulting solid was purified by amino group-modified silica gel (NH DM1020: manufactured by Fuji Silysia) column chromatography (developing solution: heptane / ethyl acetate = 1/1 (volume ratio)), and finally And 9-([1,1′-biphenyl] -3-yl) -2,7-bis (3- (pyridin-3-yl), which is a compound represented by the formula (1-1-1202). Phenyl) -9H-carbazole (0.7 g) was obtained.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.90 (m, 2H), 8.61 (dd, 2H), 8.25 (d, 2H), 7.90 (m, 2H), 7.87 (M, 1H), 7.83 (s, 2H), 7.60-7.75 (m, 11H), 7.54 (m, 4H), 7.43 (t, 2H), 7.36 ( m, 3H).

Synthesis of 2,7-bis (4-ethoxynaphthalen-1-yl) -9H-carbazole 2,7-dibromo-9H-carbazole (20 g), (4-ethoxynaphthalen-1-yl) boronic acid (33.2 g) ), Pd (PPh ₃ ) ₄ (2.1 g), and tripotassium phosphate (52.3 g) were charged with toluene (150 ml) and water (15 ml) under an argon atmosphere at reflux temperature for 2 hours. Stir. The reaction solution was cooled to room temperature, an ethylenediaminetetraacetic acid (EDTA) aqueous solution was added, and the precipitate was collected by suction filtration. The obtained solid was washed with methanol, recrystallized from chlorobenzene, and further washed with toluene to obtain 2,7-bis (4-ethoxynaphthalen-1-yl) -9H-carbazole (22.6 g). .

Synthesis of 2,7-bis (4-ethoxynaphthalen-1-yl) -9-phenyl-9H-carbazole 2,7-bis (4-ethoxynaphthalen-1-yl) -9H obtained as described above -Carbazole (22.5 g), bromobenzene (10.4 g), palladium acetate (0.2 g), tri-t-butylphosphine (0.5 g), tripotassium phosphate (28.2 g) and xylene (200 ml) The flask was stirred at reflux temperature for 12 and a half hours under an argon atmosphere. The reaction solution was cooled to room temperature, an ethylenediaminetetraacetic acid (EDTA) aqueous solution was added, and the precipitate was collected by suction filtration. The obtained solid was washed with methanol, dissolved in heated chlorobenzene, and filtered while hot using a Kiriyama funnel covered with activated alumina. Crystals precipitated by gradually distilling off the obtained filtrate under reduced pressure were collected by suction filtration, and 2,7-bis (4-ethoxynaphthalen-1-yl) -9-phenyl-9H-carbazole (21 0.8 g) was obtained.

Synthesis of 4,4 ′-(9-phenyl-9H-carbazol-2,7-diyl) bis (naphthalen-1-ol) 2,7-bis (4-ethoxynaphthalene-1) obtained as described above -Il) -9-phenyl-9H-carbazole (21.8 g), pyridine hydrochloride (86.0 g) and a flask containing N-methylpyrrolidone (25 ml) were stirred in an oil bath heated to 220 ° C. for 11 hours. did. The reaction solution was cooled to room temperature and washed repeatedly with water and methanol warmed to about 75 ° C., whereby 4,4 ′-(9-phenyl-9H-carbazole-2,7-diyl) bis (naphthalene-1- All) (19.3 g) was obtained.

Synthesis of (9-phenyl-9H-carbazole-2,7-diyl) bis (naphthalene-4,1-diyl) bis (trifluoromethanesulfonate) 4,4 ′-(9- Phenyl-9H-carbazol-2,7-diyl) bis (naphthalen-1-ol) (19.3 g) was dissolved in pyridine (100 ml) under a nitrogen atmosphere and cooled with ice water. Trifluoromethanesulfonic anhydride (31.0 g) was added dropwise thereto, and the mixture was stirred at room temperature for 22 hours after completion of the dropwise addition. Water was added and the precipitate was obtained by suction filtration. The resulting precipitate was washed with water and then with methanol. Further, it was purified by activated alumina column chromatography (developing solution: toluene), and (9-phenyl-9H-carbazole-2,7-diyl) bis (naphthalene-4,1-diyl) bis (trifluoromethanesulfonate) (18 0.5 g) was obtained.

Synthesis of 9-phenyl-2,7-bis (4- (pyridin-3-yl) naphthalen-1-yl) -9H-carbazole (9-phenyl-9H-carbazole-2, obtained as described above) 7-diyl) bis (naphthalene-4,1-diyl) bis (trifluoromethanesulfonate) (3.0 g), 3-pyridineboronic acid (1.2 g), Pd (PPh ₃ ) ₄ (0.2 g) and N, N-dimethylformamide (18 ml) was added to a flask containing tripotassium phosphate (3.2 g) under an argon atmosphere, and the mixture was stirred at 110 ° C. for 7 and a half hours. The reaction solution was cooled to room temperature, an ethylenediaminetetraacetic acid (EDTA) aqueous solution was added, and the precipitate was collected by suction filtration. The obtained precipitate was washed with methanol, dissolved in heated chlorobenzene, and filtered while hot. The obtained filtrate was distilled off under reduced pressure and purified by amino group-modified silica gel (NH DM1020: manufactured by Fuji Silysia) column chromatography (developing solution: toluene / ethyl acetate = 10/1 (volume ratio)), and finally, 9-phenyl-2,7-bis (4- (pyridin-3-yl) naphthalen-1-yl) -9H-carbazole (0.9 g) which is a compound represented by the formula (1-1-98) Got.

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.81 (m, 2H), 8.71 (dd, 2H), 8.34 (d, 2H), 8.07 (m, 2H), 7.87 (M, 4H), 7.64 (m, 2H), 7.59 (m, 4H), 7.44-7.55 (m, 12H), 7.38 (t, 1H).

Synthesis of 9-phenyl-2,7-bis (4- (pyridin-4-yl) naphthalen-1-yl) -9H-carbazole (9-phenyl-9H-carbazole-2,7-diyl) bis (naphthalene- 4,1-diyl) bis (trifluoromethanesulfonate) (2.0 g), 4-pyridineboronic acid (1.2 g), Pd (dba) ₂ (0.1 g), tricyclohexylphosphine (0.1 g) and N, N-dimethylacetamide (12 ml) was added to a flask containing tripotassium phosphate (3.2 g) under an argon atmosphere, and the mixture was stirred at reflux temperature for 10 hours and a half. The reaction solution was cooled to room temperature, an ethylenediaminetetraacetic acid (EDTA) aqueous solution was added, and the precipitate was collected by suction filtration. The obtained precipitate was washed with methanol, and then purified by activated alumina column chromatography (developing solution: toluene / ethyl acetate = 10/1 (volume ratio)). The compound represented was 9-phenyl-2,7-bis (4- (pyridin-4-yl) naphthalen-1-yl) -9H-carbazole (0.4 g).

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.76 (m, 4H), 8.34 (d, 2H), 8.06 (m, 2H), 7.91 (m, 2H), 7.64 (D, 2H), 7.59 (m, 4H), 7.45-7.55 (m, 14H), 7.38 (t, 1H).

Synthesis of 2,7-bis (3-methoxyphenyl) -9H-carbazole 2,7-dibromo-9H-carbazole (30 g), 3-methoxyphenylboronic acid (35.1 g), PdCl ₂ {P (t-Bu ) _2- (p-NMe ₂ -Ph)} ₂ (Johnson Massey, Pd-132) (0.32 g) and potassium carbonate (51.0 g) were placed in a flask containing toluene (185 ml) under an argon atmosphere. ) And water (18 ml) were added and stirred at reflux temperature for 1.5 hours. The reaction solution was cooled to room temperature, and ethyl acetate and water were added for liquid separation. The solid obtained by distilling off the solvent under reduced pressure was purified by silica gel column chromatography (developing solution: toluene / ethyl acetate = 10/1 (volume ratio)) to obtain 2,7-bis (3-methoxyphenyl) -9H. -Carbazole (35.0 g) was obtained.

Synthesis of 9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -2,7-bis (3-methoxyphenyl) -9H-carbazole 2,7-bis (3-methoxyphenyl) -9H-carbazole (10.0 g), 5′-bromo-1,1 ′: 3 ′, 1 ″ -terphenyl (12.2 g), palladium acetate (0. A flask containing 12 g), tri-t-butylphosphine (0.32 g), tripotassium phosphate (16.8 g) and xylene (88 ml) was stirred at reflux temperature for 20 hours under an argon atmosphere. The reaction solution was cooled to room temperature, and an aqueous solution of ethylenediaminetetraacetic acid (EDTA) was added for liquid separation. The solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (developing solution: toluene). Methanol was added to the oil obtained by distilling off the solvent under reduced pressure to perform reprecipitation, and 9-([1 , 1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -2,7-bis (3-methoxyphenyl) -9H-carbazole (11.5 g).

Synthesis of 3,3 ′-(9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -9H-carbazol-2,7-diyl) diphenol The resulting 9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -2,7-bis (3-methoxyphenyl) -9H-carbazole (11.5 g) and pyridine A flask containing hydrochloride (121.0 g) was stirred in an oil bath heated to 210 ° C. for 10 hours. The reaction solution was cooled to room temperature and washed repeatedly with water and methanol to give 3,3 ′-(9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -9H. -Carbazole-2,7-diyl) diphenol (10.6 g) was obtained.

(9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -9H-carbazol-2,7-diyl) bis (3,1-phenylene) bis (trifluoromethanesulfonate ) 3,3 ′-(9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -9H-carbazole-2,7- Diyl) diphenol (10.6 g) was dissolved in pyridine (53 ml) under a nitrogen atmosphere and cooled with ice water. Trifluoromethanesulfonic anhydride (15.6 g) was added dropwise thereto, and the mixture was stirred at room temperature for 16 hours after completion of the dropwise addition. Water was added, and the precipitate was collected by suction filtration. The obtained precipitate was washed with water and then with methanol. Further purification was performed by silica gel column chromatography (developing solution: toluene / heptane = 1/1 (volume ratio)). The solvent was distilled off under reduced pressure and reprecipitation was performed by adding methanol to the resulting oily component to obtain (9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -9H— Carbazole-2,7-diyl) bis (3,1-phenylene) bis (trifluoromethanesulfonate) (12.7 g) was obtained.

Synthesis of 9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -2,7-bis (3- (pyridin-3-yl) phenyl) -9H-carbazole (9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -9H-carbazol-2,7-diyl) bis (3,1-phenylene) Bis (trifluoromethanesulfonate) (4.0 g), 3-pyridineboronic acid (1.4 g), Pd (dba) ₂ (0.15 g), tricyclohexylphosphine (0.12 g) and tripotassium phosphate (4 0.0 g) was added with N, N-dimethylacetamide (20 ml) under an argon atmosphere and stirred at 120 ° C. for 5 hours. The reaction solution was cooled to room temperature, an ethylenediaminetetraacetic acid (EDTA) aqueous solution was added, and the precipitate was collected by suction filtration. Subsequently, it was dissolved in toluene, and water was added for liquid separation. The solvent was distilled off under reduced pressure and purified by amino group-modified silica gel (NH DM1020: manufactured by Fuji Silysia) column chromatography (developing solution: toluene / ethyl acetate = 20/1 (volume ratio)), and then recrystallized from toluene. 9-([1,1 ′: 3 ′, 1 ″ -terphenyl] -5′-yl) -2,7-bis (3- (pyridin-3-yl) phenyl) -9H-carbazole (1.2 g )

The structure of the compound obtained by NMR measurement was confirmed.
¹ H-NMR (CDCl ₃ ): δ = 8.90 (m, 2H), 8.60 (dd, 2H), 8.27 (d, 2H), 7.96 (m, 1H), 7.91 (M, 2H), 7.85 (m, 5H), 7.68-7.73 (m, 6H), 7.63 (dd, 2H), 7.54 (m, 5H), 7.46 ( t, 4H), 7.33-7.41 (m, 4H).

By appropriately changing the raw material compound, another carbazole compound of the present invention can be synthesized by a method according to the synthesis example described above. In addition, the compounds of the present invention include those in which at least a part of the hydrogen atoms are substituted with deuterium. Such a compound can be obtained by using a raw material in which a desired position is deuterated. It can be synthesized in the same way.

Hereinafter, examples will be shown to describe the present invention in more detail, but the present invention is not limited to these examples.

The electroluminescent elements according to Example 1 and Comparative Example 1 were manufactured, the driving start voltage (V) in the constant current driving test, the time (h) for maintaining the luminance of 90% (1800 cd / m ² ) or more of the initial luminance, and The external quantum efficiency at 1000 cd / m ² was measured. Hereinafter, examples and comparative examples will be described in detail.

Note that the quantum efficiency of a light-emitting element includes an internal quantum efficiency and an external quantum efficiency. The ratio of external energy injected as electrons (or holes) into the light-emitting layer of the light-emitting element is converted into photons purely. What is shown is the internal quantum efficiency. On the other hand, the external quantum efficiency is calculated based on the amount of photons emitted to the outside of the light emitting element, and some of the photons generated in the light emitting layer are absorbed inside the light emitting element. The external quantum efficiency is lower than the internal quantum efficiency because it is continuously reflected and is not emitted outside the light emitting element.

The external quantum efficiency is measured as follows. A voltage / current generator R6144 manufactured by Advantest Corporation was used to apply a voltage at which the luminance of the element was 1000 cd / m ² to cause the element to emit light. Using a spectral radiance meter SR-2A manufactured by TOPCON, the spectral radiance in the visible light region was measured from the direction perpendicular to the light emitting surface. Assuming that the light emitting surface is a completely diffusing surface, the value obtained by dividing the measured spectral radiance value of each wavelength component by the wavelength energy and multiplying by π is the number of photons at each wavelength. Next, the number of photons in the entire wavelength region observed was integrated to obtain the total number of photons emitted from the device. The value obtained by dividing the applied current value by the elementary charge is the number of carriers injected into the device, and the number obtained by dividing the total number of photons emitted from the device by the number of carriers injected into the device is the external quantum efficiency.

Table 1 below shows the material structure of each layer in the electroluminescent devices according to the manufactured Example 1 and Comparative Example 1.

In Table 1, “CuPc” is copper phthalocyanine, “NPD” is N, N′-diphenyl-N, N′-dinaphthyl-4,4′-diaminobiphenyl, and compound (A) is 9-phenyl-10- [6 -(1,1 ′; 3,1 ″) terphenyl-5′-yl] naphthalen-2-ylanthracene, compound (B) is N ⁵ , N ⁵ , N ⁹ , N ⁹ -7,7-hexaphenyl -7H-benzo [c] fluorene-5,9-diamine, compound (C) is 9,10-bis (4- (pyridin-4-yl) phenyl) anthracene, and “Liq” is 8-quinolinol lithium . The chemical structure is shown below.

<Example 1>
<Device Using Compound (1-1-856) for Electron Transport Layer>
A glass substrate of 26 mm × 28 mm × 0.7 mm (manufactured by Optoscience Co., Ltd.) obtained by polishing ITO deposited to a thickness of 180 nm by sputtering to 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Vacuum Kiko Co., Ltd.), and a molybdenum vapor deposition boat containing CuPc, a molybdenum vapor deposition boat containing NPD, and a compound (A) are placed therein. Molybdenum deposition boat, molybdenum deposition boat containing compound (B), molybdenum deposition boat containing compound represented by formula (1-1-856), molybdenum deposition boat containing Liq A boat, a molybdenum boat containing magnesium, and a tungsten evaporation boat containing silver were installed.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was depressurized to 5 × 10 ⁻⁴ Pa, first, the vapor deposition boat containing CuPc was heated to deposit to a film thickness of 50 nm to form a hole injection layer, and then NPD was contained. The vapor deposition boat was heated and vapor-deposited so that it might become a film thickness of 30 nm, and the positive hole transport layer was formed. Next, the vapor deposition boat containing the compound (A) and the vapor deposition boat containing the compound (B) were heated at the same time to form a light emitting layer by vapor deposition to a film thickness of 35 nm. The deposition rate was adjusted so that the weight ratio of compound (A) to compound (B) was approximately 95 to 5. Next, the evaporation boat containing the compound represented by the formula (1-1-856) was heated and evaporated to a thickness of 15 nm to form an electron transport layer. The deposition rate of each layer was 0.01 to 1 nm / second.

Thereafter, the evaporation boat containing Liq was heated to deposit at a deposition rate of 0.01 to 0.1 nm / second so as to have a film thickness of 1 nm. Next, a boat containing magnesium and a boat containing silver were heated at the same time and evaporated to a film thickness of 100 nm to form a cathode. At this time, the deposition rate was adjusted so that the atomic ratio of magnesium and silver was 10: 1, and the cathode was formed so that the deposition rate was from 0.1 nm to 10 nm to obtain an organic electroluminescent device.

When a direct current voltage was applied using the ITO electrode as the anode and the magnesium / silver electrode as the cathode, blue light emission with a wavelength of about 460 nm was obtained. In addition, a constant current driving test was performed at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 5.07 V, and the time for maintaining the luminance of 90% (1800 cd / m ² ) or more of the initial luminance was 212 hours. Moreover, the external quantum efficiency in 1000 cd / m < ² > of this element was 7.25%.

<Comparative Example 1>
<Device using Compound (C) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 1 except that the compound represented by the formula (1-1-856) was changed to the compound represented by the compound (C). When a direct current voltage was applied using the ITO electrode as the anode and the magnesium / silver electrode as the cathode, blue light emission with a wavelength of about 455 nm was obtained. In addition, a constant current driving test was performed at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 4.64 V, and the time for maintaining the luminance of 90% (1800 cd / m ² ) or more of the initial luminance was 42 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 6.58%.

The above results are summarized in Table 2.

Electroluminescent devices according to Examples 2 to 9 and Comparative Examples 2 to 4 were manufactured, and the driving start voltage (V) in the constant current driving test and the luminance of 80% (1600 cd / m ² ) or more of the initial luminance were maintained. Measurement of the external quantum efficiency at a time (h) and 1000 cd / m ² . Hereinafter, examples and comparative examples will be described in detail. The method for measuring the external quantum efficiency is as described above.

Table 3 below shows the material structure of each layer in the devices according to Examples 2 to 9 and Comparative Examples 2 to 4.

In Table 3, “HI” refers to N ⁴ , N ^{4 ′} -diphenyl-N ⁴ , N ^{4 ′} -bis (9-phenyl-9H-carbazol-3-yl)-[1,1′-biphenyl] -4, 4′-diamine, compound (D) is 9-phenyl-10- (4-phenylnaphthalen-1-yl) anthracene, and compound (E) is 2,7-di ([2,4′-bipyridine] -6- Yl) -9-phenyl-9H-carbazole, compound (F) is 9,10-bis (4- (pyridin-4-yl) naphthalen-1-yl) anthracene, and compound (G) is 9,10-bis ( 4- (Pyridin-2-yl) phenyl) anthracene.

<Example 2>
<Device Using Compound (1-1-854) for Electron Transport Layer>
A glass substrate of 26 mm × 28 mm × 0.7 mm (manufactured by Optoscience Co., Ltd.) obtained by polishing ITO deposited to a thickness of 180 nm by sputtering to 150 nm was used as a transparent support substrate. This transparent support substrate is fixed to a substrate holder of a commercially available vapor deposition apparatus (manufactured by Showa Vacuum Co., Ltd.), and a molybdenum vapor deposition boat containing HI, a molybdenum vapor deposition boat containing NPD, and compound (D) are placed therein. Molybdenum deposition boat, molybdenum deposition boat containing compound (B), molybdenum deposition boat containing compound (1-1-854), molybdenum deposition boat containing Liq, magnesium A molybdenum boat and a tungsten evaporation boat containing silver were installed.

The following layers were sequentially formed on the ITO film of the transparent support substrate. The vacuum chamber was depressurized to 5 × 10 ⁻⁴ Pa, and first, a vapor deposition boat containing HI was heated and vapor-deposited to a film thickness of 40 nm to form a hole injection layer, and then NPD was contained. The vapor deposition boat was heated and vapor-deposited to a film thickness of 25 nm to form a hole transport layer. Next, the vapor deposition boat containing the compound (D) and the vapor deposition boat containing the compound (B) were heated at the same time to form a light emitting layer by vapor deposition to a film thickness of 25 nm. The deposition rate was adjusted so that the weight ratio of compound (D) to compound (B) was approximately 95 to 5. Next, the evaporation boat containing the compound (1-1-854) was heated and evaporated to a thickness of 20 nm to form an electron transport layer. The deposition rate of each layer was 0.01 to 1 nm / second.

Thereafter, the evaporation boat containing Liq was heated to deposit at a deposition rate of 0.01 to 0.1 nm / second so as to have a film thickness of 1 nm. Next, a boat containing magnesium and a boat containing silver were heated at the same time to form a cathode with a thickness of 100 nm. At this time, the deposition rate was adjusted so that the atomic ratio of magnesium and silver was 10: 1, and the cathode was formed so that the deposition rate was from 0.1 nm to 10 nm to obtain an organic electroluminescent device.

When a direct current voltage was applied using the ITO electrode as the anode and the magnesium / silver electrode as the cathode, blue light emission with a wavelength of about 460 nm was obtained. Further, when a constant current driving test was performed with a current density for obtaining an initial luminance of 2000 cd / m ² , the driving test start voltage was 6.23 V, and the luminance was 80% (1600 cd / m ² ) or more of the initial luminance. The holding time was 170 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 4.39%.

<Example 3>
<Device Using Compound (1-1-855) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was replaced with the compound (1-1-855). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The drive test start voltage was 5.16 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 321 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 6.79%.

<Example 4>
<Device Using Compound (1-1-856) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was replaced with the compound (1-1-856). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test starting voltage was 4.84 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 198 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 5.29%.

<Example 5>
<Device Using Compound (1-1-851) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was replaced with the compound (1-1-851). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 4.83 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 334 hours. Moreover, the external quantum efficiency in 1000 cd / m < ² > of this element was 5.01%.

<Example 6>
<Device Using Compound (1-1-852) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was replaced with the compound (1-1-852). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 5.08 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 289 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 6.59%.

<Example 7>
<Device Using Compound (1-1-853) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 2, except that the compound (1-1-854) was replaced with the compound (1-1-853). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The drive test starting voltage was 4.03 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 229 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 6.89%.

<Example 8>
<Device Using Compound (1-1-98) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was changed to the compound (1-1-98). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The drive test start voltage was 5.51 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 235 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 5.95%.

<Example 9>
<Device Using Compound (1-1-99) for Electron Transport Layer>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was replaced with the compound (1-1-99). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 6.35 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 186 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 4.91%.

<Comparative Example 2>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was changed to the compound (E). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The drive test start voltage was 3.57 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 114 hours. Moreover, the external quantum efficiency in 1000 cd / m < ² > of this element was 5.20%.

<Comparative Example 3>
An organic EL device was obtained in the same manner as in Example 2 except that the compound (1-1-854) was changed to the compound (F). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 3.61 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 120 hours. Moreover, the external quantum efficiency in 1000 cd / m < ² > of this element was 5.12%.

<Comparative Example 4>
An organic EL device was obtained by the method according to Example 2 except that the compound (1-1-854) was replaced with the compound (G). A constant current driving test was performed using an ITO electrode as an anode and a magnesium / silver electrode as a cathode at a current density for obtaining an initial luminance of 2000 cd / m ² . The driving test start voltage was 4.05 V, and the time for maintaining the luminance of 80% or more of the initial luminance was 135 hours. In addition, the external quantum efficiency of this device at 1000 cd / m ² was 6.20%.

The above results are summarized in Table 4.

According to a preferred aspect of the present invention, it is possible to provide an organic electroluminescent element that improves the lifetime of the light emitting element and has an excellent balance with the driving voltage, a display device including the organic electroluminescent element, and a lighting device including the organic electroluminescent element. it can.

DESCRIPTION OF SYMBOLS 100 Organic electroluminescent element 101 Substrate 102 Anode 103 Hole injection layer 104 Hole transport layer 105 Light emitting layer 106 Electron transport layer 107 Electron injection layer 108 Cathode

Claims

A carbazole compound represented by the following formula (1-1).

In the above formula (1-1),
R is aryl having 6 to 24 carbons or heteroaryl having 2 to 24 carbons, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons;
Hy 1 and Hy 2 are each independently an electron-accepting nitrogen-containing heteroaryl having 2 to 24 carbon atoms, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. Yes,
Ar 1 and Ar 2 are each independently aryl having 6 to 24 carbon atoms which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons;
At least one hydrogen atom in the carbazole compound represented by the formula (1-1) may be substituted with deuterium.
R is phenyl, biphenylyl, terphenylyl, quaterphenyl, naphthyl, phenyl-substituted naphthyl, phenanthrolinyl, pyridyl, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group selected from the group consisting of bipyridyl, terpyridyl, quinolinyl, isoquinolinyl, pyrimidinyl, pyrazinyl, pyridazinyl and triazinyl;
Hy 1 and Hy 2 are each independently pyridyl, bipyridyl, terpyridyl, pyrimidinyl, pyrazinyl, triazinyl, azaind, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. Lydinyl, benzoimidazolyl, benzothiazolyl, benzoxazolyl, indazolyl, purinyl, carbolinyl, naphthyridinyl, quinoxalinyl, quinolinyl, isoquinolinyl, pyridylquinolinyl, pyridylisoquinolinyl, acridinyl, phenanthrolinyl, phenazinyl and imidazopyridinyl A group selected from the group consisting of:
Ar 1 and Ar 2 are each independently benzene, naphthalene, anthracene, naphthacene, pentacene, biphenyl, acenaphthylene, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons, A divalent group having a structure selected from the group consisting of fluorene, phenalene, phenanthrene, triphenylene, pyrene and perylene,
The carbazole compound according to claim 1.
R is phenyl, biphenylyl, terphenylyl, quaterphenyl, naphthyl, phenyl-substituted naphthyl, phenanthrolinyl, pyridyl, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group selected from the group consisting of quinolinyl and isoquinolinyl;
Hy 1 and Hy 2 are each independently pyridyl, bipyridyl, terpyridyl, pyrimidinyl, pyrazinyl, triazinyl, azaind, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group selected from the group consisting of lysinyl, benzimidazolyl, benzothiazolyl, benzoxazolyl, quinolinyl, isoquinolinyl, pyridylquinolinyl, pyridylisoquinolinyl and imidazopyridinyl;
Ar 1 and Ar 2 are each independently benzene, naphthalene, anthracene, pyrene, triphenylene, fluorene, biphenyl, which may be substituted with alkyl having 1 to 6 carbon atoms or cycloalkyl having 3 to 6 carbon atoms, and A divalent group of a structure selected from the group consisting of perylene,
The carbazole compound according to claim 1.
R is selected from the group consisting of groups represented by the following formulas (R-1) to (R-20), which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group to be selected,

Hy 1 and Hy 2 are each independently groups represented by the following formulas (Hy-1-1) to (Hy-1-3), and the following formulas (Hy-2-1) to (Hy-2-). 18) a group selected from the group consisting of groups represented by the following formulas (Hy-3-1) to (Hy-3-27):

Ar 1 and Ar 2 each independently represents a divalent structure selected from the group consisting of benzene and naphthalene, which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons Which is the basis of
The carbazole compound according to claim 1.
R is selected from the group consisting of the groups represented by the above formulas (R-1) to (R-14), which may be substituted with alkyl having 1 to 6 carbons or cycloalkyl having 3 to 6 carbons. A group to be selected,
Hy 1 and Hy 2 are each independently groups represented by the above formulas (Hy-1-1) to (Hy-1-3), and the above formulas (Hy-2-1) to (Hy-2-). 18) a group selected from the group consisting of groups represented by:
Ar 1 and Ar 2 are each independently 1,2-phenylene, 1,3-phenylene, 1,4-phenylene, 1,4-naphthalene-diyl, 1,5-naphthalene-diyl, 2,6- A divalent group selected from the group consisting of naphthalene-diyl and 2,7-naphthalene-diyl,
The carbazole compound according to claim 1.
The carbazole compound according to claim 5, wherein Hy 1 and Hy 2 are the same, and Ar 1 and Ar 2 are the same.
The carbazole compound according to claim 1, which is represented by the following formula (1-1-856).
The following formula (1-1-854), formula (1-1-855), formula (1-1-851), formula (1-1-852), formula (1-1-853), formula (1- 1-1198), formula (1-1-1202), formula (1-1-98), formula (1-1-99) or formula (1-1-1455) Carbazole compounds.
An electron transport material comprising the compound according to any one of claims 1 to 8.
The electron transport containing the electron transport material of Claim 9 arrange | positioned between a pair of electrode which consists of an anode and a cathode, the light emitting layer arrange | positioned between this pair of electrodes, and the said cathode and this light emitting layer An organic electroluminescent device having a layer and / or an electron injection layer.
At least one of the electron transport layer and the electron injection layer further contains at least one selected from the group consisting of quinolinol-based metal complexes, pyridine derivatives, bipyridine derivatives, phenanthroline derivatives, borane derivatives, and benzimidazole derivatives. The organic electroluminescent element according to claim 10.
At least one of the electron transport layer and the electron injection layer may further include an alkali metal, alkaline earth metal, rare earth metal, alkali metal oxide, alkali metal halide, alkaline earth metal oxide, alkaline earth Containing at least one selected from the group consisting of metal halides, rare earth metal oxides, rare earth metal halides, alkali metal organic complexes, alkaline earth metal organic complexes and rare earth metal organic complexes, The organic electroluminescent element according to claim 11.
A display device comprising the organic electroluminescent element according to any one of claims 10 to 12.
An illumination device comprising the organic electroluminescent element according to any one of claims 10 to 12.